Growth and Dry-weight Distribution in Callistephus chinensis as Influenced by Lighting Treatment

Plants of two cultivars of Callistephus chinensis (Queen ofthe Market and Johannistag) were grown in 8 h of daylight perday with one of the following treatments given during the 16h dark period: (a) darkness—‘uninterrupted night’,(b) I h of light in the middle of the dark period—a ‘nightbreak’, (c) I min of light in every hour of the dark period—‘cycliclighting’, (d) light throughout—‘continuouslight’. The plants receiving uninterrupted dark periods remained compactand rosetted in habit with small leaves, while leaf expansion,stem extension, and flower initiation were promoted in all threeillumination treatments (b, c, d). Although these three treatmentsproduced similar increases in leaf area, continuous light wasthe most effective for the promotion of both stem growth andflower initiation while cyclic lighting was generally more effectivethan a I-h night break. Continuous light also caused more dry matter to be divertedto stems at any given vegetative dry weight and it was shownthat the stem weight ratio of both varieties was correlatedwith stem length.     

Behavioral responses of the brittle star Ophiura ophiura to amino acids, acetylcholine and related low-molecular-weight compounds

Feeding behavior of the brittle star Ophiura ophiura includesorienting posture, orienting movements, arm ‘walking’,changing the direction of ‘walking’ arm coilingand ingestion. All sequential behavior patterns were releasedor enhanced by single low-molecular-weight compounds. Stimuliwhich released ‘walking’ behavior at high concentrations(10^–4 M) in all the test animals are listed in decreasingorder of sensitivity: sarcosine, glycine, urea, L-valine, L-leucine,L-methionine, L-homocysteine, L-norvaline, L-norleucine, L-threonine,L-serine, S-methyl-L-cysteine, L-proline. Threshold values forsingle amino acids were as much as 100 times different in differentindividuals and ranged from 3 x 10^–9 to 3 x 10^–7M for the most effective stimulus, sarcosine, and from 10^–6to 10^–4 M for proline. Above 10^–5 M, only L-prolineregularly released a second behavior pattern, the arm coilingresponse, which temporarily inhibited the ‘walking’behavior. Behavioral thresholds for the ‘walking’behavior for L(+)-lactate and L-alanine were higher than thosefor the orienting movements. Thyoglycolic acid and ß-alaninereleased tube feet walking, which is not part of the feedingbehavior. Structure—activity comparisons were studied at estimated10^–5 M concentrations. Gycline, sarcosine, L-valine, L-norvaline,L-leucine, L-isoleucine, DL-norleucine and DL-homocysteine releasedarm ‘walking’ behavior in more than 75% of all thetests. With the exceptions of S-methyl-and S-ethyl-cysteine,and glycine methylester, derivatives of amino acids were noteffective behavioral stimuli in Ophiura ophiura. L-Isomers ofvaline and leucine regularly stimulated the ‘walking’behavior while their D-isomers were effective in some testsand ineffective in others. Acetylcholine iodide, acetyl-ß-methylcholine chloride and choline phosphate chloride regularly released‘walking’ behavior at concentrations above 10^–5M.     

ERRATA

Effects of coupled solute and water flow in plant roots withspecial reference to Brouwer's experiment. Edwin L. Fiscus. p. 71 Abstract: Line 3 delete ‘interval’ insert‘internal’. p. 73 Materials and Methods: line 6: delete ‘diversion’ insert ‘division’ line 9 equation should read J_v=L_p P–RT(C⁰–C¹). 74 Last line of figure legend: 10^–1 should read 10^–11. 75 Line 11: delete ‘seems’ insert ‘seem’. le 1 column heading—10⁶ should read 10¹¹. 77 delete ‘...membrane in series of...’ insert ‘membranein series or...’ Delete final paragraph.     

ERRATA

WARBURG, M. R., 1965. On the water economy of some Australianland snails. Proc. malac. Soc. Lond. 36, 297–305. Page 298: second line from bottom, should read ‘within± 1 µg for Themapupa’. Page 300: Fig. 2 legend, should read ‘Evaporative waterloss from Sinumelon remissum (a), Pleuroxia sp. (b) and Themapupaadelaidae (c)’. Page 300: section 4 heading, should read ‘Continuous curvesfor water loss’. Page 301: second line, for ‘Fig. 9’ read ‘Fig.3’. Page 301: Table 1, last line, for ‘0.120024’ read‘0.12024’. Present address: Israel Institute for Biological Research, Ness-Ziona,Israel.     

Physiological and Ecological Studies in the Analysis of Plant Environment: VII. An Analysis of the Differential Effects of Light Intensity on the Net Assimilation Rate, Leaf-Area Ratio, and Relative Growth Rate of Different Species

Since relative growth rate is the product of net assimilationrate and leaf-area ratio (leaf area/plant weight), it followsthat if the effects of shading on both net assimilation rateand leaf-area ratio can be expressed mathematically, then therelationship between light intensity and relative growth ratecan be derived from the product of the two mathematical expressions. For all the ten species investigated in field and pot cultureexperiments, it has been found that during the early vegetativephase both the changes in leaf-area ratio and net assimilationrate, over the range of 0·1 to full daylight, are linearlyrelated to the logarithm of the light intensity. In consequence,the relationship between relative growth rate and the logarithmof light intensity—being the product of the two linearregressions—is curvilinear. For species of shady habitats (Geum urbanum, Solamun dulcamara)neither the levels of assimilation rate nor the ‘compensation-point’values are very different from those of the eight species fromopen situations (e.g. Hordeum vulgare, Pisum sativum, Fagopyrumesculentum). Nevertheless the intensity at which growth rateis maximal varies between species: it is 0•5 for G. urbanum,0•7 for H. annuus, full daylight for F. esculentum, whilefor Trifolium subterraneum the calculated value is 1·8daylight. Such specific differences can be largely accountedfor in terms of the differences in leaf-area ratio at the differentlight levels. On the basis of this analysis of the light factor, a ‘shade’plant is best redefined as a species in which a reduction ofthe light intensity causes a rapid rise in the leaf-area ratiofrom an initial low value in full daylight: for a ‘sun’plant the converse definition holds.     

The Nitrogen Content of Plants and the Self-thinning Rule of Plant Ecology: A Test of the Core-skin Hypothesis

The ‘core-skin’ hypothesis postulates that secondarilythickened plants behave energetically as an inert ‘core’covered by an active ‘skin’, the ‘skin’being two-imensional, the ‘core’ three-dimensional.This would explain the ‘self-thinning ‘or‘–3/2’ rule of plant ecology, that is, the tendencyfor log (dry weight per plant) and log (number of plants perunit area) to progress along a straight line relationship, withslope = – 3/2’. The hypothesis was tested as follows. Plant nitrogen contentwas used as an estimate of the mass of ‘skin’ perplant, and dry weight as an estimate of the mass of the ‘core’.As plants mature the slope of the relationship between y = log(mass of nitrogen per plant) and x = log (mass of dry matterper plant) is expected to decline from an initial value of 1.0towards a final value of 0.66. The intercept of the relationshipis expected to reflect the intrinsic content of ‘skin’per unit of ‘core’. Genotypic variation in thisparameter should cause genotypic differences in the maximumattainable yield of biomass per unit area. The expectations were investigated by fitting the function y= p+qx+r exp – x to 30 sets of data on plant nitrogencontent, plant weight and time in 18 different vegetables. Simplelinear regressions of y on x were fitted to more limited setsof data on weights and nitrogen contents of mature trees. Theexpectations were, with some minor exceptions, confirmed. Nitrogen, yield, plant competition, self-thinning     

Effects of Monochromatic Radiations on Growth of Pelargonium Callus Tissue

Pith callus tissues were grown under continuous blue (450 mµ),green (545 mµ), red (650 mµ), and ‘white’(full-spectrum) light, and in the dark for 22 days at 27±2°C at energy levels of 15,000 ergs cm^–2 sec^–1. Mean increases in fresh weight of tissues grown under ‘white’and blue light were significantly greater than those of tissuesgrown in green and red light and in the dark. Tissues grownin the dark yielded mean fresh weight increases significantlylower than tissues grown under blue, red, and ‘white’light. No significant differences were shown between blue and‘white’, red and green, and green and dark treatmentsrespectively. Cell differentiation occurred in all treatmentsonly to the extent of vessel element formation. There were nodifferences in degree of differentiation between treatments. It was proposed that the high-energy reaction of photomorphogenesiswas in operation in the Pelargonium callus tissue. The resultsindicated the presence in the tissue of high-energy photoreceptor(s).The use of high-intensity, incandescent illumination for experimentalprocedures approximating natural conditions of irradiation wasindicated as desirable for pith callus tissues of Pelargoniumzonale var. Enchantress Fiat.     

CORRECTIONS, VOLUME 29

Part 1, under the frontispiece portrait of Dr. N. B. Eales,the words ‘President 1948–1951’ should havebeen added. Page 103, line 49, for ‘Newton Collection’ read‘Norman Collection (Canon Norman)’. 185, line 37, for ‘capillaris’ read ‘capillacca’. 188, Table 1, for ‘bemoralis’. read ‘nemoralis’. 188, Table 2, for ‘Cochlicella acuta (Müll)? ventrosa(Fér.)’ read ‘Cochlicella ventrosa (Fér.)’. 191, line 24, for ‘araheo-’ read ‘archeo-’.     

Studies in the Bangioideae III. The Life-history of Porphyra umbilicalis (L.) Kutz. var. lociniata (Lightf.) J. Ag.: A. The Conchocelis-Phase in culture

As the first step in an investigation of the life-history ofPorphyra umbilicalis (L.) Kütz. var. laciniata (Lightf.)J. Ag., spores which have originated as a result of the repeateddivision of the mother-cells have been germinated. When grownon glass their method of germination and growth agrees withthat described by previous investigators, but when germinatedon sterile shell the germ-tubes penetrate the shell and developinto growths identical with Conchocelis rosea Batters. This‘species’, therefore, is a phase in the life-historyof P. umbilicalis var. laciniata and not an autonomous species.The development of the ‘Conchocelis’-phase in cultureis described and also the formation of fertile cell-rows and‘plantlets’. Until the significance of these structuresis understood and a cytological investigation completed, therelationship of the intertidal leafy Porphyra-thallua to thefilamentous, shell-inhabiting, deep-water Conchocelis cannotbe expressed in the terms usually employed to denote the variousphases of the life-histories of algae.     

Structural and Histochemical Changes in Palisade Cells of Prosopis juliflora Seed Coat in Relation to its Water Permeability

Histochemical investigations on the Prosopis juliflora seedcoat indicate the occurrence of a hydrophobic ‘strip’as the primary water barrier. Its position and the structureand histochemistry of the palisade cells of the seed coat differaccording to their location on the seed. These differences maybe responsible for differences in the water permeability ofvarious parts of the seed coat. In particular, parts of theseed coat in which the hydrophobic ‘strip’ is locatedmore superficially tend to be more water impermeable than partslike the chalaza, in which the ‘strip’ is more deeplylocated within the palisade cells. Prosopis juliflora, seed coat impermeability, palisade cells, hydrophobic ‘strip’     

Some Early Responses of Helianthus annuus L. to Flooding: I. THE EFFECTS OF FLOODING ON THE UPTAKE AND LEAKAGE OF 'NON-ELECTROLYTES' BY ROOTS

Drakeford, D. R., Mukherjee, I. and Reid, D. M. 1985. Some earlyresponses of Helianthus annuus L. to flooding. I. The effectsof flooding on the uptake and leakage of ‘non-electrolytes’by roots.—J. exp. Bot. 36: 1705–1715. The object of this work was to examine some of the early effectsof flooding on roots. A hydroponic system was developed thatgave good control over watering, degree of oxygenation of thebathing medium and allowed measurement of short term changesin the composition of the bathing medium. Excised roots, floodedfor 24 h, were shown to take up less [³H) ß-alaninethan non-flooded roots and also leaked more [³H] ß-alanineinto a distilled water bathing medium. Further, flooded excisedroots lost more protein to the bathing medium, with ‘young’(5–7 d) roots showing greater losses than ‘old’(11–14 d) roots. However, young roots had more proteinin the tissue even after greater loss. Young roots remainedhealthier and lost less fresh weight than old roots. Abscisicacid was shown to have a small role in protecting ‘young’roots from the effects of flooding. Key words: ABA, abscisic acid, anaerobic, flooding, leakage, roots, uptake, waterlogging     

Further Observations on Fungi Inhabiting Pine Stumps

Growth-rates, both on malt agar and in stump wood, of earlystump colonizers such as Fomes annosus, Pemophora gigantea,Stereum sanguinolentum, and Leptographium lundbergii are higherthan those of later-colonizing agarics. The initial invasionof stump roots usually proceeds via the stump body by fungiwhich infect the cut surface. Although stumps may dry out appreciably shortly after felling,in later stages of decay the moisture content of the wood oftenincreases considerably. Stump decomposition is associated witha succession of decay fungi, the ‘Peniophora’, ‘Hypholoma’,and ‘Tricholoma’ stages being distinguished. Severalphycomycetes and fungi imperfecti colonize decayed, but notfresh, stump wood. P. gigantea is shown to be a vigorous competitor of F. annosusfor initial colonization of stumps: it may also replace F.annosus in stumps. Gliocladium viride and Trichoderma viridecompete with wood-rotting basidiomycetes and sometimes replacethem in very decayed wood.     

The Effects of Salinity upon Galactosyl-Glycerol Content and Concentration of the Marine Red Alga Porphyra purpurea (Roth) C.Ag.

Changes in the major alcohol-soluble, low molecular weight carbohydratesof P. purpurea, O--D-galactopyranosyl-(1-2)-glycerol (‘floridoside’)and O--D-galactopyranosyl-(1-1)-glycerol (‘isofloridoside’),have been examined in response to salinity variation. ‘Floridoside’is shown to vary in absolute amount, increasing in hypersalineand decreasing in hyposaline media. ‘Isofloridoside’content per cell does not change in a similar manner. Responsesare almost identical under light or dark conditions, ‘floridoside’changes being complete within 24 h. Decreasing the externalwater potential using ionic and non-ionic solutes has the sameeffect upon galactosyl-glycerol content. The amount of ‘floridoside’synthesized, and degraded under hypersaline and hyposaline conditionsrespectively is shown to be insufficient to restore cell volumeto its original value. It is therefore suggested that the primaryfunction of ‘floridoside’ increases in concentratedsea-waters is that of a compatible solute, serving to protectthe cell during periods when the external salt content is increaseddramatically.     

The Sensitivity of Light Modulation of Enzyme Activity to Arsenite and Sulphite and of Photosynthetic Induction toArsenite is Determined by a Cytoplasmic Gene

Muschinek, G., Alscher, R. and Anderson, L. E. 1987. The sensitivityof light modulation of enzyme activity to arsenite and sulphiteand of photosynthetic induction to arsenite is determined bya cytoplasmic gene—J. exp. Bot. 38: 1069–1075. The membrane component of the light modulation system was moresensitive to arsenite and to sulphite in the Pisum cultivar‘Nugget’ than in the cultivar ‘Progress No.9’. Likewise, the induction phase of CO₂ fixation wasmore arsenite sensitive in chloroplasts isolated from ‘Nugget’plants. Sensitivity was controlled by a cytoplasmic gene. Key words: Induction, light modulation, arsenite sensitivity     

The Influence of the Plant Growth-regulator, 2-Methyl-4-Chlorophenoxyacetic Acid, on the Metabolism of Carbohydrate, Nitrogen and Minerals in Solanum lycopersicum (Tomato)

The effects of the foliar application of phytocidal concentrationsof 2-methyl-4-chlorophenoxyacetic acid (MCPA) on change in totaldry weight, and in ‘available carbohydrate’ (starch,‘total’ and ‘reducing’ sugars), totalnitrogen, phosphorus, potassium, calcium, and magnesium of ‘tops’and roots of tomato plants have been followed over a periodof 14 days following spraying. There were two main treatments—‘nutrient’(nutrient supply to roots continued after spraying) and ‘water’(distilled water only supplied to roots after spraying) and‘water’ (distilled water only supplied to rootsafter spraying)—the sub-treatments consisting of ‘MCPA’versus ‘no-MCPA’ for each of the main treatments.Twelve different times of sampling were used. In analysing the present data, the quantity ‘residualdry weight’ (total dry weight less ‘available carbohydrate’),which was originally introduced by Mason and Maskell as a basisof reference for analyses of plant organs in short-period experimentsnot involving appreciable growth, has been used as an estimateof the permanent structure of plant growth. This new use ofthe ‘residual dry weight’ basis has brought outimportant features which were obscured when the data were leftin their primary form (as percentages of total dry weight oramounts per plant). Growth, as measured by increase in ‘residual dry weight’,was greatly inhibited by 2-methyl-4-chlorophenoxyacetic acidshortly after spraying, in both the presence and the absenceof nutrient. In the presence of 2-methyl-4-chlorophenoxyacetic acid, netassimilation rate (estimated as rate of increase in total dryweight per gram ‘residual dry weight’ of the ‘tops’)was greatly diminished while uptake of total nitrogen and ofP₂O₅ (estimated as increase in total nitrogen or of P₂O₅ ofthe whole plant per day per 1 g. ‘residual dry weight’of the roots) appeared to undergo a similar but much smallerdiminution. It seemed probable, however, that in the presenceof MCPA a larger proportion of the carbohydrate actually formedwas utilized for synthesis of aminoacids and protein. In the plant as a whole there was no evidence of actual depletionof ‘available carbohydrate’ as a result of MCPAtreatment, this fraction showing a steady increase in all treatmentsthroughout the experiment. The rate of increase was, however,much reduced by MCPA treatment. The ‘tops’ presentedmuch the same picture as the whole plant, but for the rootsthe situation was quite different. While the roots of the ‘no-MCPA’plants and also of the ‘MCPA-water’ plants showeda steady increase in available carbohydrate, those of the ‘MCPA-nutrient’plants rose only very slightly (from the initial value of 8mg. per plant to about 10 mg.) during the first 2 days, andthen in the next 2 days declined to a value (about 6 mg.) belowthe initial and remained at this low level for the rest of theexperiment. It is suggested that the phytocidal effect of 2-methyl-4-chlorophenoxyaceticacid in the presence of nutrient may be due to depletion ofthe ‘available carbohydrate’ supplies in the roots,which is shown to be brought about, in part, by reduced transportfrom the tops, and partly by the relatively greater utilizationof the carbohydrate present. These results offer an explanationfor the facts that plants showing vigorous growth are more easilykilled by MCPA and that perennial plants, particularly thosewith storage tissues in their roots, are more resistant. Further,they suggest the useful practical application that MCPA treatmentshould be given when the carbohydrate reserves of the rootsare at a minimum. For perennial plants, conditions might beexpected to be optimal for the application of MCPA in late spring,at a time when the first ‘flush’ of growth is slowingdown and before any appreciable new reserves of carbohydratehave been accumulated. It was also shown that 2-methyl-4-chlorophenoxyacetic acid preventedthe net synthesis of starch, but still permitted an appreciablenet formation of sucrose. 2-methyl-4-chlorophenoxyacetic acid appeared to have no effecton the uptake of potassium, calcium, or of magnesium. The lackof effect on potassium is contrasted with the previous observationby Rhodes, Templeman, and Thruston (1950) that sub-lethal concentrationsof MCPA, applied over a relatively long period to the rootsof tomato plants, specifically depressed the uptake of potassium.     

Sunflower Seed Proteins: Characterization and Subunit Composition of the Globulin Fraction

Salt soluble proteins from sunflower (Helianthus annuus) seedswere fractionated by isoelectric precipitation and analysedby electrophoresis. Three molecular species were detected bygradient polyacrylamide gel electrophoresis of the globulinfraction. Multi-dimensional gel electrophoresis analysis indicatesthat all these species contained similar intermediary subunitsof 60 000, 54 000, 48 000 and 40000 molecular weight, the twoformer being predominant. As shown by ion-exchange chromatographyunder dissociating and reducing conditions, the intermediarysubunits are composed of disulphide linked pairs of large ‘acidic’and small ‘basic’ subunits. Heterogeneity in molecularweight of these subunits was shown by electrophoretic studies.These results suggest that a major reserve protein in sunflowerseeds is similar to ‘legumin’ of plants of the familyLeguminosae. Key words: Sunflower, Seed globulin, Globulin subunits     

The Adaptation of Dunaliella to Widely-Differing Salt Concentrations

Methods are described for adapting pure cell-lines of Dunaliella,a green unicellular alga, to grow at concentrations between0.5 M and 3.5 M NaCl. It is shown that, provided large abruptchanges are avoided, cells of the same cell-line can becomeadapted to grow over this wide range of salt concentration.Once adapted, cultures are able to continue growing at a steadyrate for many generations provided that the salt concentrationremains constant. Viability tests performed after abrupt changesin salt concentration have shown that survival is higher afterdownward than after upward changes (3.5 M to 0.5 M NaCl: 20%;0.5 M to 3.5 M NaCl: 0.01% in D. parva 19/9). When the changein concentration from 0.5 M to 3.5 M NaCl takes place over aperiod of 48 h viability approaches 100%. The time needed for100% survival for a downward change over the same range is only1.5 h. There is no evidence for a genetic difference betweencell-lines adapted to particular concentrations of salt andit is concluded that the so-called ‘halophilic’and ‘halotolerant’ strains are interchangeable.It seems likely that the difference between the two types isa matter of gene expression. Key words: Dunaliella, salt concentration, viability     

Factors Affecting the Abscission of Reproductive Organs in Yellow Lupins (Lupinus luteus L.): III. ENDOGENOUS GROWTH SUBSTANCES IN VIRUS-INFECTED AND HEALTHY PLANTS AND THEIR EFFECT ON ABSCISSION

Extracts of small and mature-size lupin pods yielded four substancesaffecting the growth of wheat-coleoptile sections: one acidpromotor (A), two acid inhibitors(B and X), and one neutralinhibitor(Y). Inhibitor B was extremely active, however, coleoptile sectionsshowed no signs of toxic effects; they resumed growth at a rapidrate after rinsing them and adding ß-indolylaceticand (IAA) to the medium. 1 µg of IAA was required to counteractthe effect of ‘B’ extracted from 230 mg. Of tissue.On an equal fresh weight basis the inhibiting action of ‘B’in lupin pods was 500–1,500 times more potent than thatof ‘inhibitor ß’ in etiolated pea seedlings. Small pods of plants infected with pea-mosaic virus yielded3 times the amount of ‘A’ of healthy plants (equivalentto 1 µg. IAA 0.3 µg. IAA per 25 g. of tissue respectively),and approximately the amount of ‘B’. Mature podsof virus-infected plants again yielded more‘A’,but also 2? times more ‘B’ than pods of healthyplants. Healthy pods yielded more ‘A’ than virus-infectedpods, and there was no difference in ‘X’. A lupin abscission test was developed and the effects of proximaland distal application of -naphthyl acetic acid (NAA) are presented,and discussed with respect to results of other abscission tests. ‘A’ accelerated abscission when applied proximally,and delayed or prevented it when applied distally. ‘B’strongly accelerated abscission when applied in either way.A possible mechanism explaining the abscission-inducing effectof developing pods on later flowers is discussed in terms ofthe substances ‘A’ and ‘B’. The partlyprevented abscission observed on virus-infected plants was foundto agree well with the proposed mechanism.     

REPRODUCTIVE CYCLES OF CERASTODERMA GLAUCUM(BRUGUIERE) AND C. EDULE (L.) WITH SPECIAL REFERENCE TO THE EFFECTS OF THE 1981-82 SEVERE WINTER

Gonadal changes in two species of Cerastoderma occurring indiscrete populations in South Wales were monitored by stereologicalanalysis during the breeding seasons of 1981 and 1982. Fecundityand spawning efficiencies were determined quantitatively. Therelationship between reproductive activity and changes in meatcondition are discussed. Both species are opportunistic breeders. Their normal patternsof reproduction are similar, consisting of minimum activityin winter and peak activity during spring/early summer. Thetwo species were affected differently by the severe winter of1981–82—C. glau-cum exhibited a single, ‘epidemic’spawning and resumed gametogenesis after a 4-month resting period.C. edule adopted a ‘polycyclic’ pattern withouta resting period. Both of these unusual reproductive strategies,augmented by reduced predation resulted in heavy spatfalls. (Received 20 March 1985; revised 20 March 1985;     

The Histology of Seed Development in Diploid and Tetraploid Raspberries (Rubus idaeus L.)

Ovules of the raspberry, Rubus idaeus L., resembled those ofother Rubus species in being unitegmic, crassinucellate, andanatropous. In one cultivar, ‘M. 69/139’, both eggcell and embryo were inserted slightly laterally to the micropyle.Of the tetraploid forms, 4n M. 69/139 showed a proportion ofembryo sacs with delayed differentiation, and 4n ‘M. Jewel’some with four antipodal cells. Embryo development showed littleuniformity in timing, but followed the Asterad type. Occasional delayed endosperm development seemed to be a varietalpeculiarity of M. 69/139. At maturity, the ergastic materialin healthy endosperms consisted of oil globules and aleurongrains. The hypostase formed a projecting pedestal below theendosperm at 8 days. The inner epidermal layer of the testaappeared specialized, both in the early stages of seed growth,when it is suggested that it functioned as an endodermis, andat maturity, when it appeared to form an osmotic barrier.