1. The present studies deal with the cytochemical observations in the normal and X-irradiated spermatogenesis of Stenobothrus viridulus. 2. The nucleus of the normal cell contains basic proteins, DNA, and acid mucopolysaccharides containing carboxyl groups only. The nuclear membrane, however, shows the presence of lipids. In the irradiated nucleus, the site of DNA and basic proteins are clearly marked, the former aggregated along the nuclear membrane while the latter concentrated in the centre. 3. The mitochondria and the mitochondrial nebenkern of the normal material consist of tyrosine and arginine. The outer membrane of the nebenkern has acidic lipids and cholesterol. In the irradiated material, the intensity of the reactions increased with the coagulation of the proteins. They can now be differentiated with the lipoidal membrane. 4. The Golgi bodies consist of galactogen, acid mucopolysaccharides (sulphuric acid groups only), and acidic lipids. In the irradiated material, the polysaccharides lose the staining power while the lipids form the outer membrane. 5. The acrosome is PAS positive and also contains tyrosine. The latter becomes more pronounced in the abnormal material. 6. The centriole region consists of lipids plus proteins. The latter coagulate in the irradiated material and is clearly differentiated from the lipids.
1. The peripheral blood of the normal goldfish, Carassius auratus, contains erythrocytes, thrombocytes, lymphocytes, neutrophils, eosinophils, and basophils. Immature stages of these elements are frequently encountered in the blood. Detailed descriptions and illustrations of these cells have been presented. 2. The mean erythrocyte count of 100 goldfish was 2, 025, 000±118, 671/mm3, and the mean thrombocyte count was 51, 550±3, 323/mm3. 3. Erythrocytes in an apparent state of amitotic division were observed to be numerous in the blood of certain animals which also had large numbers of erythroblasts. 4. The total leukocyte count was 21, 987±1, 519/mm3. A differential analysis of the leukocytes revealed that lymphocytes totaled 20, 323±1, 073/mm3 (92.5/); neutrophils, 1, 132±143/mm3 (5.1%); eosinophils 488±61/mm3 (2.2%); and basophils, 44±25/mm3 (0.2%). 5. No blood cells corresponding to the monocyte of higher vertebrates were observed in C. auratus.
The nuclear structures and the division process of vegetative nuclei of a strain of Saccharomyces, Schizosaccharomyces pombe, Lipomyces starkeyi, Torula utilis and Torula rubra were studied by means of various cytological methods. 1. The nucleus of all species studied contains chromatin, a single nucleolus, karyoplasm and a nuclear membrane. The chromatin was Feulgenpositive and stained with aceto-orcein and Giemsa. The nucleoli were Feulgennegative and stained with haematoxylin, aceto-carmine and Giemsa. When the materials were stained with Giemsa, the nucleoli became more reddish than the chromatin. 2. In dividing stage, the chromosomal bodies appeared. In Saccharomyces, six chromosomal bodies were recognized, though more than six were sometimes seen after pretreatment. In Schizosaccharomyces pombe, the chromatin became granular in dividing stage, but no distinct chromosomal bodies were observed. About four chromosomal bodies were recognized in Lipomyces starkeyi. Four chromosomal bodies were also recognized in Torula utilis. Granular chromosomal bodies appeared in Torula rubra, but their number was not counted. Anaphase to telophase took place on one side of the nucleoli. In Saccharomyces, the nucleoli changed the shape during these stages, but in the other four species the nucleoli kept their spherical shape during these stages. 3. After the chromatin divided, two masses of chromatin were separated to daughter cells. In this separation stage, the nucleoli of Saccharomyces and Schizosaccharomyces pombe elongated and became constricted at the midregion and separated to the daughter nuclei, while the nucleoli of Lipomyces starkeyi, Torula utilis and Torula rubra were left behind in the mother cells and disintegrated there. New nucleoli seem to be synthesized in the daughter nuclei in these three species. 4. A slender body was found, which connected two masses of separating chromatin in Torula utilis. This body seems to separate the chromatin into the daughter cells. The existence of such body was also recognized in Lipomyces starkeyi.
In the present report the localization and concentration of cytochemically demonstrable adrenaline and noradrenaline in the suprarenal medulla of normal and reserpine-treated pigeons have been described. It has been found that even a very minute dose (.05 mg/100 gm b. wt.) of reserpine can cause an almost total depletion of noradrenaline. Along with this a loss of adrenaline from the core of individual cords is also noticed. It is interesting to note that considerably high dosages (.80 mg-1.70 mg) of reserpine are unable to cause depletion of adrenaline from the peripheral zone of the chromaffin cords. The differential response of adrenaline and noradrenaline to reserpine in the pigeon suprarenal medulla has been pointed out and discussed in the light of current researches.
Seventeen species and one variety of the genus Cyrtanthus were investigated cytologically, chromosome numbers were determined, and idiograms were prepared. Twelve of these have been studied for the first time. The diploid chromosome number is sixteen for all the species investigated. The idiograms vary from asymmetric to more symmetric ones and this variation is accompanied by a change in flower shape. Both as regards karyotype and flower structure, some Cyrtanthus species are extremely similar to species of Vallota, others are karyologically almost identical to species of Anoiganthus and have perianth tubes as short of those of Anoiganthus. It is suggested that the three genera are congeneric and a new concept, which involves only minor changes, is proposed for Cyrtanthus to combine these genera. The combination Cyrtanthus herrei by Dyer (1959) is supported by cytological evidence.
The value of the HCl-Giemsa technique in the study of fungal cytology has again been demonstrated. Using this technique the cytology of the asexual stage of Monilinia fructicola has been studied with the following results. Nuclear division in the homocaryon is synchonous for all nuclei within a cell. Division appears to proceed by mitosis, the haploid chromosome number being four. The range of numbers of nuclei throughout the mycelium has been investigated. Mature conidia contain an average of 6.6 nuclei with a distribution from 4 to 10. Upon germination initially 2 to 3 nuclei move into the germ tube. The remainder divide synchronously within 24 hours incubation and about half of these subsequently move into the germ tube. Hyphal cells are generally multinucleate with a distribution of 1 to 40 nuclei per cell. Lateral branches are generally multinucleate when delimited by a septum. Hyphal tips and conidiophores are generally multinucleate. Young conidia initially receive 2 to 3 nuclei each and may receive more subsequently by the movement of nuclei from conidium to conidium in older parts of the chain. The movement of nuclei into germ tubes, into lateral branches, along anastomoses, into young conidia and through septal pores has been observed. This study has shown that the asexual stage of Monilinia fructicola has virtually every conceivable mechanical process for the production and maintenance, coupled with the possible dissociation, of a heterocaryon. The question of differential rates of nuclear division within a heterocaryotic mycelium is at present only a theoretical possibility. However, the presence of multinucleate cells; nuclear movement through septal pores, through anastomoses and between conidia; multinucleate lateral branches and hyphal tips and multinucleate conidiophores and conidia, provides for Monilinia fructicola a system of great potential flexibility in adaptation to the environment.
1. Cytological investigations as regards the morphology of the chromosomes during mitosis have been made out in two Oedogonium spp. 2. The process of nuclear division during mitosis follows a normal course and the number of chromosomes has been estimated 19 in Oedogonium cardiacum from the counts of chromatids at anaphase and in another Oedogonium sp., the number of chromosomes has been estimated as approximately 41 during late prophase. 3. The morphology of the chromosomes in regard to the position of the centromeres has been studied. Localised centromeres are easily recognisable as non staining regions at points of bending of chromatids during anaphase. As regards the positions of centromeres, the chromatids are found to be of three types, with median centromeres, sub-median centromeres and subterminal centromeres. 4. The spiral structure of the chromosomes of various sizes is easily recognisable in mid-prophase and at telophase. Ohasi (1930) has reported about the spiral structure of the chromosomes in Oedogonium grande. Delicate spindle fibres appear to be present as pointed out by Ohasi (1930). 5. The nucleus enlarges considerably during early prophase, the nuclear membrane becomes irregular and minute chromatin granules arranged in linear order, appear within whole nuclear cavity as observed by Kretschmer (1930) in Oedogonium pachyandrium. At about mid-prophase, long intertwined chromosome threads are visible, some of which are seen orientated lengthwise as pointed out by Kretschmer (1930). 6. Chromatids are easily recognisable at pre-metaphase and at metaphase, the chromosomes appear short or long rod-shaped. Anaphase follows a normal course of division and the chromatids are seen more closely crowded at both ends of poles. 7. The process of nuclear division and the structure of chromosomes of both spp. of Oedogonium appears similar to that of the higher plants. 8. The method of staining by acetocarmine has been used throughout the investigation for cytological study. 9. The sex organs were formed generally after three months in old cultures. But they were formed profusely and more rapidly within a week when they were grown in an atmosphere of carbon dioxide by placing the filaments in watch glasses enclosed in petri-dishes containing 5% sodium bicarbonate as reported by Starr (1955). 10. After inoculation in fresh culture solutions, zoospores were produced within 4 days. The male and female filaments of Oedogonium cardiacum were inoculated singly in culture media and zoospores were seen to be produced from them.
The notable effects of commercially available nucleic acids, their salts or their precursors incorporated in a culture medium on the mitotic pattern of cultured cells of Vicia faba L. under liquid shaking conditions have been reported. The cell aggregates growing in a control medium showed only an occasional abberration. In a medium containing nucleic acids or their salts, certain of the cell aggregates revealed evidence for the occurrence of fragmentation, formation of micronuclei, the so-called “reductional groupings” and other chromosomal abberrations. In terms of percentage, these were few. One notable and well-pronounced effect was that in presence of nucleic acids or their salts in the culture medium, there was a high incidence of polyploid cells at different stages of division. When cell aggregates were incubated in a medium containing nucleic acid precursors (thymidine, cytidine or uridine), there was also a high incidence of polyploid cells in active stages of division. This was very appreciable in the cytidine and uridine-treated cultures. Giant cells and giant nuclei were also seen very frequently in these cultured cells. Certain of the giant cells were seen in metaphase stages in cytidine- and uridine-treated cultures. From the evidence obtained in this study as well as from other workers, it is suggested that observations such as the occurrence of “reductional groupings” may not have any relationship between an additional supply of nucleic acids in a culture medium and the occurrence of reduction-division processes in somatic cells. The possibilities of using tissue culture techniques in studying mitotic processes in polyploid cells seem to be promising from this stucy.