A Carmine-Giemsa Staining Technic For Meiotic Prophase Chromosomes Of The Genus Beta L

For a detailed study of chromosome morphology in meiotic prophase stages of Beta species, a special double staining technic has been developed. It consists of combined maceration-staining in an ethanol-hydrochloric acid-carmine mixture followed by poststaining of the squashed material in a diluted Giemsa solution. The technic yields well-spread prophase meiotic nuclei showing detailed structures both in weaker stained chromosome segments and in threadlike chromatin structures. This technic proved to be especially favorable for stages which are difficult to interpret, such as pachytene, schizotene and diffuse stages.     

An Aceto-Carmine Squash Technic for Mature Embryo Sacs

A method is described by which, whole embryo sacs of Nicotiana, Petunia and no doubt of certain other genera can be obtained readily in aceto-carmine ovule squashes. Although application of the technic to megagametogenesis and fertilization stages is stressed in this paper, use of the method allows development to be traced from the archespore up to the second or third division of endosperm nuclei. The success of the technic depends on four phases:-1) fixation in a medium that causes cell and nuclear structures to become pliable, yet rigid enough that their spatial relationships are not greatly distorted in squashing; 2) heat, which apparently increases the cohesion of cytoplasmic and nuclear constituents; 3) maceration to separate the embryo sac from surrounding cells; and 4) the use of a stain that differentiates the various nuclear structures as well as those of the cytoplasm. Staining of the cytoplasm, essential in some embryological investigations, is one advantage of the aceto-carmine squash method over the Feulgen procedure. In contrast to the Feulgen ovule squash method the aceto-carmine technic will probably be most useful in genera having numerous small ovules. Advantages and defects of the aceto-carmine procedure as compared with the paraffin technic are discussed, likewise the possible usefulness of the former in studies of sterility and in certain other special connections.     

Improvements of Hagmann's Method for Injecting Insect Tracheae

A simple technic for holding and releasing the specimen cage under vacuum by means of paraffin and heat is described. The technic is very easy to follow and greatly facilitates the handling of large numbers of specimens. The specimen cage used is illustrated and the use of a household detergent, Tide, in substitution of Santomerse for preparing Hagmann's solution A is mentioned.     

A Rapid Histological Technic for Staining Latex in Roots of Taraxacum Kok-Saghyz

The freezing technic described in this paper provides permanent slides of sections of the root of Taraxacum kok-saghyz with latex preserved in place. The following schedule is used: (1) Prefreeze the piece to be sectioned before removal from the root. (2) Mount in ice and section with chilled microtome knife. (3) Plunge frozen sections into the combination coagulant and stain prepared from Calco oil blue N. A., acetic acid and ethyl alcohol. (4) Wash in water. Aspirate if necessary. (5) Mount on a slide using Karo.

This technic is rapid and simple. The sections are well adapted to making counts and measurements of latex tubes since there has been a minimum of latex loss. Latex is retained in place by keeping tissues frozen until introduced into the coagulant.     

Water-Pretreatment Squash Technic: A New and Simple Practical Method for the Chromosome Study of Animals

To simplify the staining of animal chromosomes (especially in insect testes) the authors have borrowed (with necessary modifications) the squash technic of plant cytology. The method has four steps: (1) Water pretreatment. This step requires only about 5-10 minutes either in water at room temperature or in water kept at about 38°C. in a water bath. (2) Fixation. Ordinarily only 5 minutes in 10-15% aqueous solution of glacial acetic acid is necessary. (3) Staining. The fixed tissue is rinsed in two or three changes of distilled water and then placed in a solution of basic fuchsin: either 1% in 30% ethyl alcohol, or 0.2-0.4% in 5-10% lactic acid. In the former solution the staining period should be about 2 minutes: in the latter, 5-20 minutes. The time is not critical. (4) Squashing. The material is rinsed in several changes of distilled water, placed on a clean slide and squashed under a cover glass. Such preparations last 4-5 weeks, and a technic is described for removing the cover glass in order to mount in Euparal and to make them permanent. The authors list various species of vertebrates as well as invertebrates in which the technic has given good chromosome staining, as shown by illustrations.     

A Flagella Staining Technic for Soil Bacteria

In an attempt to stain the flagella of soil bacteria, many of which have flagella so fine that they are hard to stain by most methods, a technic was developed which combines the best points of Hofer and Wilson's method with that of Bailey as developed by O'Toole. Satisfactory preparations have been obtained for organisms of the genera Pseudomonas, Phytomonas, Alcaligenes, Escherichia, Azotobacter, and Bacillus. This technic, therefore, is recommended as a rapid and constant method for routine flagella staining of all motile aerobic organisms; it combines Hofer and Wilson's method of cleaning the slides with O'Toole's technic of spreading the smears and with a modification of Bailey's mordant.     

Histochemical Localization OF Acid Phosphatase IN Germinating Maize Kernels

Sections of germinating maize kernels obtained by freezing technic were examined for acid phosphatase according to the histochemical method of Gomori. The embryonic axis, scutellum and aleurone layer were found positive for the enzyme. A microtechnical method for preformed phosphate, based on Sumner's colorimetric method for phosphorus, is described.     

Culture of Pollen Tubes for Chromosomal Analysis at the Pollen Tube Division

It is possible to grow pollen tubes routinely for cytological analysis of nuclei at the pollen tube division. Pollen has been grown successfully after temperature, pressure, gas, moisture, and radiation treatments. The technic for growing Tradescantia pollen is described, but any method is satisfactory which ensures that: (a) the pollen is kept dry before sowing, (b) a minimum of time elapses between sowing pollen on culture medium and placing in a moist growing box, and (c) the growing pollen tubes are not allowed to dry out. Pollen of other species can be grown by the same methods.     

Cuticular ultrastructure of Chordodes nobilii Camerano, 1901, with a comparison of cuticular ultrastructure in horsehair worms (Nematomorpha)

The cuticle of Chordodes nobilii Camerano, 1901 is composed of a proximal layer with about 30 sheets of large fibers in alternating orientations and a distal layer, which mainly forms the surface structures, the areoles. The three different types of areoles, simple, tubercle and crowned areoles, are formed mainly by material of strong and medium electron density. The tubercle areoles have a basal constriction and paired spherical structures of unknown function below the base. Irregularly distributed are paired, cushion-like structures, from which projections traverse the cuticle and run into the epidermis. In the crowned areoles, these cushions also send projections into the apical filaments. A comparison with the few ultrastructurally described cuticles from other species reveals some similarities between the cuticles of C. nobilii and Paragordius varius, making it probable that the cushion-like structures are homologous. However, Pseudochordodes bedriagae, which is more closely related to Chordodes than Paragordius, lacks the cushions. Problematic is the interpretation of different cuticular structures in Gordius. If correctly determined, areoles are present in some Gordius species and resemble in their structure areoles from other species. If areoles have to be regarded as homologous, the absence of a distal layer and areoles would have to be interpreted as a secondary reduction in species such as Gordius aquaticus.     

New evidence for laurasian corystosperms: Umkomasia from the Upper Triassic of Northern China

Recent finds of remarkable fossil plants from the Upper Triassic Yangcaogou Formation in Liaoning Province, PR China include branched, cupule-bearing structures referable to the corystosperm ovulate organ Umkomasia. This material is described and assigned to the proposed new species Umkomasia asiatica. The collection includes numerous isolated cupules and fragments of ultimate cupule-bearing axes. Two specimens consisting of portions of the main axis with attached, cupulate lateral axes have also been found. The main axis was at least 6.5 cm long, with each lateral axis bearing one to at least three pairs of stalked, ovoid cupules. The new Umkomasia is similar to U. franconica from the Jurassic of Germany, which is the only other known laurasian species, but the cupules are smaller and more elongated. It is also similar to many gondwanan forms, including the type species U. macleanii. Leaves associated with the Chinese Umkomasia species are tentatively referred to Thinnfeldia, and may have been produced by the same plant. Associated ovoid seeds with elongated, curved micropyles are similar to those of gondwanan species of Umkomasia. The fossils described here are, therefore, significant in representing the first report of corystosperm reproductive structures from Asia, and only the second report of Umkomasia from the entire northern hemisphere. The new Chinese fossils also support leaf-based evidence that the Corystospermales were present in Laurasia as early as the Late Triassic.     

The Feulgen Reaction After Hydrolysis at Room Temperature

Among the cytochemical methods for demonstrating desoxyribonucleic acid, the hydrochloric-acid-Schiif reaction has been valuable since Feulgen reported it in 1924. A difficulty in that technic is that the section may come loose from the slide; this is caused by hydrolysis at 60° C. When sections were hydrolyzed by 1, 3, 5 or 6 N HCl at room temperature for 15 minutes, adequate hydrolysis and the strong development of color occurred with 5 N HCl. Similarly successful results were obtained with 5 N nitric acid hydrolysis for 10 minutes. Both procedures appear to be as practical as hydrolysis in 1 N HCl at 60° for 4-6 minutes.     

A METHOD FOR THE QUANTITATIVE ESTIMATION OF CYTOPLASMIC STRUCTURES

A sampling procedure and calculations are described by which electron micrographs of cytoplasmic structures may be quantitatively analyzed. The relative areas occupied by formed bodies and by the "membrane space," the remainder of the cytoplasm, are evaluated. A method for making a measurement of the quantity of endoplasmic reticulum or other membrane profiles is described. The technic and results are illustrated with normal rat liver cells.     

Root-Tip Smear Method for Difficult Material

A technic is outlined for the preparation of difficult material for the study of chromosome number and morphology in root-tip smears. The chief objective is to obtain polar views of the metaphase plates rather than equatorial views. To achieve this end it is recommended that fresh root-tips be cut free-hand into thin cross sections. The important features are: thin freehand cross sectioning of the fresh root-tips; fixing in Belling's iron aceto-carmine solution; maceration for 2-5 minutes in 50% HCl in 95% alcohol; and mounting in “Diaphane.”     

Stability of the Gram Reaction

In the course of about 7000 examinations of Gram-positive aerobic bacteria, it was found that two distinct groups of Gram-positive organisms could be recognized. One group was illustrated by Micrococcus freudenreichii, the other by Bacillus anthracis. All individuals in a smear of the former remained positive even when the time of exposure to stain was greatly diminished and the time of exposure to decolorizer was greatly increased. Similar changes of technic when B. anthracis was used showed that about 70% of the individuals in a given smear became Gram-negative. The writer accordingly distinguishes between stable and unstable Gram-positive bacteria.     

Staining and Observing Pollen Tubes in the Style by Means of Fluorescence

Pollen tubes in the styles of the tomato and of other flowering plants can be observed by using the following technic. Styles are fixed in formalin-acetic-80% alcohol (1:1:8) and cleared and softened in a strong (8 N) sodium hydroxide solution. Staining is accomplished in a 0.1% solution of water-soluble aniline blue dye dissolved in 0.1 N, K₃PO₄. The styles are smeared or are observed whole under a conventional or dissecting microscope by direct illumination with ultraviolet light of a wavelength of about 356 m°. Observations are made in a darkened room. Under these conditions callose fluoresces bright yellow-green and contrasts strongly with the bluish or grayish fluorescence of the stylar tissue. The pollen tubes are outlined by a callose lining and irregularly spaced callose plugs.     

舌瓣鼠尾草退化杠杆雄蕊的相关花部特征及传粉机制

杠杆状雄蕊是鼠尾草属(Salvia)物种形成的关键性状, 背部杠杆传粉模式作为该属植物与传粉者精确互作的经典案例被广泛深入研究, 但是在该属物种中还存在许多非典型的杠杆结构和传粉模式。雄蕊结构及其与传粉者互作的多样性, 使得鼠尾草属成为研究植物传粉模式转变的模式材料, 舌瓣鼠尾草(S. liguliloba)即是一种具非典型的退化杠杆状雄蕊结构和传粉特征的代表性物种。该文着重对舌瓣鼠尾草的花器官结构和传粉特征进行研究, 并与具有短药隔杠杆的毛地黄鼠尾草 (S. digitaloides)做比较分析, 以期揭示退化杠杆可能的进化选择压力及其生态学意义。结果表明, 舌瓣鼠尾草具有较短的花冠、更窄的冠筒和较短的雄、雌蕊(p < 0.05)。退化萎缩的雄蕊下臂, 冠筒内的狭小空间限制了唯一的有效传粉昆虫——三条熊蜂(Bombus trifasciatus)推动雄蕊做杠杆状运动, 而是靠近花药直接利用头部完成授粉。相比经典的杠杆状雄蕊结构及其传粉过程, 小型花冠和退化杠杆雄蕊是对专一性和活跃度较高传粉昆虫的适应, 可能具有完全不同的进化途径和繁殖策略。     

A carmine-Giemsa staining technic for meiotic prophase chromosomes of the genus Beta L.

For a detailed study of chromosome morphology in meiotic prophase stages of Beta species, a special double staining technic has been developed. It consists of combined maceration-staining in an ethanol-hydrochloric acid-carmine mixture followed by poststaining of the squashed material in a diluted Giemsa solution. The technic yields well-spread prophase meiotic nuclei showing detailed structures both in weaker stained chromosome segments and in threadlike chromatin structures. This technic proved to be especially favorable for stages which are difficult to interpret, such as pachytene, schizotene and diffuse stages.     

Specific Staining of Nucleolar Substance with Aceto-Carmine

A method is described for staining nucleoli intensely by treating tissues with formaldehyde, hydrolysing in normal HC1 at 60°C. and staining with aceto-carmine. With correct hydrolysis time, chromosomes and cytoplasm are almost colorless.

Formaldehyde increases the acidity of cell parts, especially the nucleolus, presumably by neutralizing the basic protein groups, and increases the resistance to hydrolysis, perhaps by protecting the phospholipoprotein complexes which are most abundant in the nucleolus.

Hydrolysis reduces the acidity of cell parts, chiefly by removal of nucleic acids.

Aceto-carmine stains cell structures which are weakly acid in character (about pH 4-5) probably by precipitating as large dye aggregates.

The technic appears to be highly specific for nucleoli and related cell bodies.     

东亚特有属——小勾儿茶属的研究

本文对东亚特有属——鼠李科小勾儿茶属(Berchemiella)进行了比较系统地研究, 对该属的建属历史, 形态特征、木材解剖、分类及分布进行了论述。根据该属的木材构造和花粉形态等, 作者赞同中井猛之进将Berchemiella独立为属的观点。该属共有3种1变种, 在我国有2种1变种。毛柄小勾儿茶(B.wilsonii var.pubipetiolata H.Qian, 新变种)为首次描述。