COMPARATIVE MORPHOLOGY OF RADULAR TEETH IN CONUS: OBSERVATIONS WITH SCANNING ELECTRON MICROSCOPY

Radular teeth of 22 Indo-Pacific species of the genus Conus(Neogastropoda: Toxoglossa) were compared. On morphologicalfeatures all can be related to one of three known feeding modes:piscivorous, vermivorous and molluscivorous. Observations arereported on the radular teeth of six piscivores, thirteen vermivoresand three molluscivores. The radular teeth of piscivores areof two general types. In the first, two barbs and a posteriorly-directedprocess with a recurved tip are found at the anterior end. Inthe second, two barbs are located at the anterior end and theshaft is serrated for most of its length. An enlarged posteriorregion (terminal knob) is present in the first and absent inthe second. Molluscivores possess radular teeth with two anteriorbarbs and in some species a serrated shaft or terminal knob.The radular teeth of vermivores, which show much greater interspecificvariation than those of piscivores or molluscivores, are characterizedby one or two anterior barbs and in most species a serratedregion near the apex. A forwardly-projecting cone (basal spur)is usually located on the terminal knob. Piscivores and molluscivoreslack such basal spurs. The radular teeth of Conus are used toconvey a potent venom and hold prey firmly during feeding. Previouslyundescribed morphological features are noted on the teeth ofC. obscurus and C. lividus. Figured here for the first timeare the radular teeth of C. abbreviatus, C. aureus, C. catus,C. litoglyphus, C. pennaceus, C. rattus and C. sponsalis. ^*Present address: Department of Paleontology, University ofCalifornia, Berkeley, California 94720, U.S.A. (Received 2 April 1979;     

RADULAR VARIATION IN TWO SPECIES OF SPONGE-RASPING DORID NUDIBRANCHS

The damp live weight of specimens of Archidoris montereyensisand Anisodoris nobilis was found to be positively correlated( = 0.05) to the number of teeth per row, the number of rowsin the radula and the length of teeth. Covariance analyses ofthe regressions of the first two radular characteristics toweight failed to statistically separate the two species. Theseresults argue against the utility of radular information astaxonomic characters in sponge-rasping dorids. The increase in tooth size with increasing animal size was foundto be statistically divergent for these two species and wasinterpreted as being consistent with the feeding biology ofthese two species. (Received 10 March 1977;     

COMPARATIVE KARYOLOGICAL ANALYSIS OF FIVE SPECIES OF VIVIPARUS (GASTROPODA: PROSOBRANCHIA)

Karyological analysis was performed on Viviparus ater (Cristofori& Jan, 1832), V. acerosus Bourguignat, 1862, V. mamillatus (Kuster),V. viviparus (Linnaeus, 1758) and V. contectus (Millet, 1813),collected from different freshwater bodies of Switzerland, Hungary,Albania, Italy and Lithuania. The karyotypes of V. acerosusand V. mamillatus are described for the first time. The diploidnumber of chromosomes in V. contectus equals 14, whereas indiploid sets of other studied species, 18 chromosomes are present.The karyotype formula is in V. contectus (5m + 2sm, NF = 28,in V. ater, 7m + 1sm-m + 1 sm, in V. acerosus and V. viviparus,8m + 1sm, NF = 36, in V. mamillatus, 6m + 1m-sm + 1sm-m + 1sm,NF = 36. In females of V. ater, V. mamillatus and V. acerosus,the heteromorphism of chromosome pair no. 8 was observed, witha sex-determining mechanism — ZW female /ZZ male. Although,Z and W chromosomes are metacentric, significant differences(P > 0.05, or P > 0.001) in their size were determined.The interspecific significant differences (P > 0.05) in karyotypesof V. ater, V. mamillatus, V. acerosus and V. viviparus weredetected by using one-way ANOVA and Bonferronis Multiple Comparisontests. Only chromosomes of the pair no. 5 were of similar shapein all of these species. The smallest interspecific differencewas between V. viviparus and V. acerosus. The intraspecifickaryological differences in relative chromosome length and centromericindex of V. contectus from lakes Garda (Italy), Olauka andAsveja (Lithuania) were observed in the chromosome pair no.5. (Received 29 March 1999; accepted 19 October 1999)     

RADULAR PRODUCTION RATES IN TWO SPECIES OF LACUNA TURTON (GASTROPODA: LITTORINIDAE)

The molluscan radula is a dynamic organ, both in terms of itsuse and production. New rows of teeth are constantly producedat the posterior end of the radula, while older, worn teethare shed anteriorly, producing a dynamic equilibrium. We useda cold-shock to mark the radular ribbon and measure tooth rowproduction rates in two gastropod species, Lacuna vincta (Montagu)and L. vanegata Carpenter. We found that the average tooth rowproduction rate at 10–11°C did not differ betweenthese two species, and was 2.94 (SE = 0.002) rows per day forLacuna vincta and 2.97 (SE = 0 002) for L. vanegata Inter-individualvariability in production rate was very low, and was correlatedwith shell length, smaller individuals had slightly higher productionrates. The total length of the radular nbbon varied greatlyamong individuals, ranging from 47 to 94 (2.57 to 5.68 mm) rowsin L vincta and 53 to 99 rows (2.80 to 7.14 mm) in L vanegata,and was only somewhat correlated with the length of the shelLThis great variability will result in large differences amongindividuals in the time it takes to replace the radula totally,from 14.96 to 35.44 days in L vincta and from 17 43 to 39 69days in L. vanegata. (Received 1 September 1995; accepted 20 November 1995)     

四种假丝酵母与其有性型的分子核型比较*

用脉冲电泳对四种假丝酵母及各自的有性型,包括Candida guilliermondii—Pichia guilliermondii, Candida krusei—Issatchenkia orientalis, Candida naganishii—Debaryomyces nepalensis和Candida valida—Pichia membranaefaciens,进行了分子核型比较分析, 发现每对无性型-有性型酵母菌均具有相同或相似的染色体DNA分子带型, 而各对之间却具有显著差异,显示了脉冲电泳核型分析在寻找及确证酵母菌无性型-无性型关联中的应用价值。     

四种蝗虫前肠形态的比较分析(直翅目：斑腿蝗科)

该文采用体视显微摄影技术对斑腿蝗科(Catantopidae)3属4种蝗虫前肠形态进行了对比分析。结果显示：所研究的3属蝗虫云秃蝗属,蹦蝗属和无翅蝗属前肠形态有一定共性;同时也可看出,云秃蝗属和蹦蝗属更相近,体现了前肠形态特征与其他分类性状呈正相关。     

A COMPARATIVE STUDY OF THE FOLIAR ANATOMY OF LYCOPODIUM SPECIES

A comparative study of the leaves of 31 species of Lycopodium was made. The pattern of tracheids varies with the species. Usually they exhibit annular, helical, reticulate, modified or transition forms; none of the species have advanced phylogenetically beyond the scalariform tracheid stage. Mucilage canals have been found in four species. Tracheids are enclosed by a few to several layers of oblique ended, elongated parenchyma cells in most species, but an endodermis is absent. Vascular bundles are encircled by fiber cells in three species. The mesophyll of most species consists of identically shaped cells, although palisade-like tissue has been observed in a few species. The epidermal cells vary from elongated to isodiametric and have either undulated or smooth anticlinal walls, which are deeply pitted in some species. The outer epidermal walls are usually thick and heavily cutinized. Stomates are distributed on both surfaces in 18 species, on the abaxial surface in 11 species, and on the adaxial side in only two species. Most stomates are practically isodiametric in surface view, broader than epidermal cells, usually parallel to the vein, and at the same level as the adjacent epidermal cell. A typical guard cell has a prominent outer ledge and a less developed inner ledge of cutin in most species. Six groupings are suggested, based on similarity of leaf structure and the known chromosome numbers.     

A COMPARATIVE STUDY OF SEXUAL REPRODUCTION IN FOUR SPECIES OF CHLAMYDOMONAS

Trainor , Francis R. (U. Connecticut, Storrs.) A comparative study of sexual reproduction in four species of Chlamydomonas. Amer. Jour. Bot. 46(2) : 65-70. 1959.—This paper reports results of comparative experiments on some factors affecting sexual reproduction in 4 species of Chlamydomonas. Sexuality can be controlled in 3 of these species (C. chlamydogama, C. eugametos and C. reinhardti) by the level of ammonium nitrate in the harvesting medium. It was demonstrated that periodicity of illumination was of importance for high zygospore yields with C. chlamydogama and C. eugametos. Other variables, e.g., various aspects of nitrogen level, illumination and inter-fertility, were investigated and the results summarized in tabular form.     

ATTRIBUTES OF CHLOROCOCCUM SPECIES: A NUMERICAL ANALYSIS2

From previously published data, 73 characteristics of 17 species of Chlorococcum were compiled. Comparisons of character states of each character were made, and simple matching coefficients were calculated for each species by following the procedure of Sokal & Michener. From a data matrix of the matching coefficients, a phenogram was constructed according to the unweighted pair group method of Sokal & Sneath. Arithmetic averages were used in transferring data from one matrix to another. The frequency of each character state was calculated, and the character states of the highest frequency (the modes) were used to describe a “typical” Chlorococcum species. Comparisons were made between the “typical” Chlorococcum species and each of the 17 species studied. Simple matching coefficients were also calculated from these comparisons. All of the species had a relatively high affinity for the data of the calculated “typical”. Suggestions are made about the use of a “typical” taxonomic unit, and questions are raised about the taxonomic relationship among species of the genus Tetracystis and the genus Chlorococcum.     

COMPARATIVE ULTRASTRUCTURE OF CULTURED SPECIES OF TREBOUXIA1,2

Five species of cultured Trebouxia—T. anticipata, T. decolorans, T. erici, T. gelatinosa, and T. impressa—were examined with the electron microscope. A comparative examination of their pyrenoids revealed pyrenoglobuli associated with single pyrenoid thylakoids. The pyrenoids of T. decolorans, T. erici, and T. gelatinosa possess single thylakoids that cross or deeply penetrate the pyrenoid matrix and are often disposed in parallel arrays. T. anticipata possesses both single and double pyrenoid thylakoids within the matrix. T. impressa possesses vesiculate invaginations of thylakoid membranes into the pyrenoid matrix. The phycobiont. T. erici was examined in detail at the light and electron microscopic levels for pyrenoid alterations associated, with varied environmental regimes and with cell division. A greater amount of starch is present in cells grown in organic culture at 215 lux light intensity than in cells of similar size grown at 1075 or 3600 lux. Pyrenoglobuli are present throughout the life cycle and occur both in aplanospores and in zoospores.     

STARCH GEL ELECTROPHORESIS OF PLANT ISOZYMES: A COMPARATIVE ANALYSIS OF TECHNIQUES

The use of genetic information expressed in isozymic form has enhanced our understanding of heritable variation within and among plant populations. For over three decades now, protein electrophoresis coupled with histochemical staining has provided data on the concordance of observable features in plants (e.g., morphology, cytology, ecological adaptation) with isozyme phenotypes. Yet inadequate dissemination of procedural details and varied investigative approaches have limited the comparative value of electrophoretic data and have made it difficult for novices to apply the technique to other experimental systems. Information gathered from over 25 laboratories utilizing enzyme electrophoresis is treated comparatively, providing access to protocols that often are either unpublished or widely dispersed in the literature. Analyzed in the review are methods and guidelines for enzyme extraction, effective storage of plant samples and buffers, efficient screening of taxa for enzymatic activity, and interpretation of diploid and polyploid banding patterns.     

BIOGEOGRAPHY OF INDO-PACIFIC CICADOIDEA: A TENTATIVE RECOGNITION OF AREAS OF ENDEMISM

Abstract— The biogeography of the cicadas of the Indo-Pacific is discussed in relation to paleogeography and compared with distribution patterns found in other groups of organisms. The cicadas show a low degree of endemism in the mainland of southeast Asia and the Greater Sunda Islands, and a high degree of endemism in Sulawesi, New Guinea, and the islands of the west Pacific. The biogeography of the cicadas of these regions with high endemism is analyzed for four groups: the subtribe Cosmopsaltriaria, the tribe Prasiini, the genus Baeturia , and the Pacific Cryptotympanini. A review of the paleogeography of the Indo-Pacific, specifying the relevant barriers, island arcs, and land connections, is provided. The recognized areas of endemism are tentatively related to the geological history of the Indo-Pacific. Areas of endemism are the Sulawesi Arcs and the Outer and Inner Melanesian Arcs. New Guinea appears to be a composite of areas of different origin: the central mountains of the Inner Melanesian Arc, the north-coast mountains of the Outer Melanesian Arc, and the Vogelkop area, which is of uncertain origin. The Papuan Peninsula of New Guinea seems to be a zone of overlap between the Outer and the Inner Melanesian Arcs. The Pacific archipelagos of the Outer Melanesian Arcs (viz., the Bismarck Archipelago, Solomon Islands, Vanuatu, and the Fiji, Tonga, and Samoa Islands) represent distinct areas of endemism. The taxon-area cladogram of the Cosmopsaltriaria gives some indication of the relationships among the areas of endemism. The discussion is extended to groups of bats, frogs, psocids, butterflies, and moths of the Melanesian Arcs, as their patterns of distribution seem equally relevant for the recognition of the biogeographic interrelationships in the Indo-Pacific.     

A COMPARATIVE STUDY OF CHROMOSOMES IN FOUR SPECIES OF THEODOXUS (GASTROPODA: NERITIDAE)

Karyological analysis was performed on Theodoxus baeticus (Lamarck,1822), T. valentina (Graells, 1846), T. velascoi (Graells, 1846)and T. fluviatilis (Linne, 1758), collected from freshwaterbodies of eastern Spain. Cells possessing diploid chromosomenumbers of 2n 5 25 were most common in the tissues of males,whilst 2n 5 26 was most prevalent in females. The sixth pairof chromosomes had only one homologue in mitotic cells of males,indicating the XO/XX sex-determining mechanism. The absolutelength of chromosomes ranged from 1.65 to 6.33 mm. The relativesizes of chromosomes varied from 3.92 to 13.33% of the totalhaploid set length. In all species chromosome pairs no. 1, 4,7-13 were composed of metacentric, pairs no. 5 and 6of submetacentricchromosomes. Pairs no. 2 and 3 were submetacentric, subtelocentricor submeta- subtelocentric according to the species studied.There were significant differences (P, 0.05) among the relativelength, as well as centromeric indices of different chromosomepairs across the species. Karyological differences were greatestbetween T. fluviatilis and three other Theodoxus species. (Received 6 March 2000; accepted 8 May 2000)     

五种雀形目鸟类核型的比较研究

染色体核型的比较研究,对于了解物种的特性,探索物种的遗传、进化、系统发育及分类地位都有一定的意义。有关鸟类的核型研究,国外已有不少报道(Castrovicja,1969; Hammar,1966,1975; Ray-Chaudhuri et al.,1969;Shidds,1982;Ta—kagi,1972等)国内在这方面的工作开展较迟,已作过核型分析的鸟类为数不多,仅见王应祥等(1982)的报道。迄今,作过核型研究的鸟类已达500多种,其中雀形目有200种。本文比较分析了五种野生雀形目鸟类的核型,它们是黑头蜡嘴雀,斑鸫,黄腹山雀,红尾伯劳和灰背椋鸟。     

FOUR NEW SPECIES OF TAMBJA BURN, 1962 (NUDIBRANCHIA: POLYCERIDAE) FROM THE INDO-PACIFIC

The genus Tambja previously included 24 described species. Fournew species, T. tentaculata n. sp., T. gabrielae n. sp., T.zulu n. sp. and Tambja victoriae n. sp., from the Indo-Pacificare described. Tambja tentaculata n. sp., from Guam, is theonly known species in the genus with well developed, dorsolaterallygrooved, oral tentacles. Its inner lateral teeth have a bifidinner cusp with two long, sharp denticles. The oral tentaclesof T. tentaculata are more typical of Roboastra species, whilethe shape of the inner lateral teeth is more typical of Tambja.Nevertheless, the arrangement of the two cusps of the innerlateral teeth and the presence of a rachidian tooth withoutdenticles and with a central notch at the anterior edge, typicalof the species of the genus Tambja, suggest the placement withinthis genus. Tambja gabrielae n. sp., from Indonesia and PapuaNew Guinea, has dark green to dark brown ground colour withbright yellow patches scattered on the body. Tambja zulu n.sp. from Durban, South Africa, is characterized by a black groundcolour with slender yellow longitudinal lines. Tambja victoriaen. sp. is a new species from Papua New Guinea and Australiathat has frequently been misidentified as Roboastra arika, characterizedby its blue body colour and yellow lines. The four species aredistinguishable based on differences in body coloration, ofcharacters of the radula and of the reproductive system. Anoverview on distinguishing features of all known Indo-PacificTambja species is presented. (Received 21 June 2004; accepted 20 January 2005)