The morphological and cytochemical investigations of the cytoplasmic organelles of the intestinal goblet cells of rats have been carried out by employing old classical techniques and their various modifications, various other morphological and current cytochemical techniques. Mitochondria are filamentous with surface granules attached and have the usual lipoproteinous nature. Lipid granules-detached surface granules of the mitochondria-with the progress in the secretory cycle grow, become duplex and serve as sites for the condensation of the secretion products-mucus. Mucus has been chemically identified as mucopolysaccharides. Cytoplasmic PNA and its distribution during various secretory phases has been studied. Details of mucinogenesis have also been discussed in the current communication. There has not been observed anything consistently which can even remotely be compared with the classical ‘Golgi apparatus.’ The discharge of the mucus from the goblets has not been observed to be explosive and continuous but on the contrary gradual and intermittent phenomena respectively. Specificity of Hg-BPB as a general protein stain has also been discussed.
Absolute length measurements are reported for all chromosomes of 271 pachytene microsporocytes from 89 anthers of 31 related corn plants. Arm ratios are reported for all of these chromosomes where it was possible to locate the centromere. Data are compared to previously published measurements of corn chromosomes. Sample variances and coefficients of variation of chromosome lengths and arm ratios are compared. The results include findings that longer chromosome arms have greater variances but smaller coefficients of variability and that chromosomes with larger arm ratios have inherently more variable arm ratios. These greater variabilities in arm ratio were not correlated with corresponding greater variabilities in length of the chromosomes involved. All results are consistent with the interpretation that the chromosomes have two kinds of variability: one which seems to contribute approximately uniformly per unit length to variability throughout the genome while the other kind of variability may be a characteristic property of each chromosome unrelated to length in any consistent way. Chromosome knobs do not appear to influence variability in length of chromosome arms in which they occur. Tripsacum chromosome material does not appear to differ in its length variability from corresponding corn chromosome material for which it has been substituted.
Chromosomes were counted in 10 Oryza species; 8 of them were diploid (2n=24): O. sativa, O. fatua, O. glaberrima, O. stapfti, O. perennis, O. longistaminata, O. officinalis and O. brachyantha; 2 were tetraploid: O. schweinfurthiana and O. latifolia. The morphology of the chromosomes was similar and their size was not very different: the chromosomes of O. officinalis were significantly larger than those of every other species; the ones of O. brachyantha were very small. The meiosis was regular in the diploid species; 0-4 quadrivalents were seen at diakinesis in O. schweinfurthiana and O. latifolia (on an average 0.64 in both species). It is assumed that the origin is monophyletic. There are indications of homology among the 12 haploid chromosomes, but there is no sufficient evidence of the existence of a definite basic number lower than 12. The tetraploid species are more or less strict allopolyploids.
In the present investigation there is described the existence of a new cellular element of the tissue-cells of Mimosa pudica and that of several other leguminous plants. 1. Carotenoid-bodies in the main pulvinus, petiole and in the mesophyll of the leaf are chiefly dealt with. 2. Fixed with neutral formalin, the carotenoid-body is marked stained with brilliant cresyl blue. It must be remarked here that the carotenoid-body gradually developed in the cytoplasm of young tissue-cells. 3. Carotenoid-bodies are uniformly distributed throughout the tissuecells of main pulvinus, petiole and of the mesophyll of the leaf. 4. By the author's method, carotenoid-bodies in the diurnal condition are observed to be more inflated than those in the nocturnal condition. 5. Carotenoid-bodies gradually dissolve in 70 to 100 per cent ethanol, and attenuate, leaving no trace. 6. By treatment in iodine solution, the carotenoid-body appears indigobrown in color. 7. The carotenoid-body proved reacted positively to Carr-Price reagent, . which is probably closely related to its photo-physiological function. 8. The carotenoid-bodies in the fresh material when observed clearly with a phase contrast microscope, are spherical in shape. 9. In the tissue-cells of the pulvinules of Desinodium gyrans, Wistaria floribunda and Robinia pseudo-Acacia, the carotenoid-bodies are distributed as in the Mimosa. 10. Judging from the data obtained by these observations, it is concluded that the carotenoid-body is one of the cellular elements, and is by no means a mere artifact.
In order to compare Oryza species regarding the pattern of secondary association in meiosis, PMC's of O. sativa, O. sativa f. spontanea, O. glaberrima, O. breviligulata, O. officinalis, O. australiensis, O. brachyantha, O. ridleyi and O. subulata were observed. Of these species, O. ridleyi is allotetraploid (n=24), while the rest are diploid (n=12). The results may be summarized as follows: 1) All diploid species showed the same type of maximum secondary association, 2(3)+3(2). Also in the mean number of secondary associations per cell, they showed no significant difference. 2) The pattern of secondary association in O. ridleyi could be accounted for on the same basis as for the diploid species. The frequency distribution of cells with different numbers of secondary associations did not fit the Poisson distribution, in the same manner as formerly pointed out by the writer for O. sativa and O. glaberrima. 3) It was concluded that these facts would be in favor of the hypothesis of secondary polyploidy of Oryza, and the doubling of genetic materials in remote ancestry might have played an important role in the evolution of the genus.
Echinochloa colona (L.) Link of Malaya and Java, and Indian strains of cultivated species, E. frumentacea (Roxb.) Link, were certained to be hexaploid, n=27, and to have the same genome constitution in common. Although the F1 hybrids of these two species showed a low degree of fertility, it can be assumed that E. colona is a wild form of E. frumentacea. In earlier paper the author (Yabuno 1953) has confirmed that hexaploid varieties of E. crus-galli (L.) Beauv. and Japanese cultivated strains have the same genome constitution, and that the former is a wild form of the latter. Four F1 hybrids between Indian strains of E. frumentacea and hexaploid varieties of E. crus-galli, and an F1 hybrid between Indian strain of E. frumentacea and Chinese cultivated strain were cytologically investigated. It is concluded that E. colona and E. crus-galli do not possess genomic constitution in common. The same conclusion can be adopted to Indian and Chino-Japanese cultivated strains. But any genomic formula was not assigned to these species in this paper. Indian and Chino-Japanese cultivated strains have been maintained under the specific name, E. frumentacea. On the basis of the results of cytological investigations Chino-Japanese cultivated species was separated from E. frumentacea, and the new specific name, E. utilis Ohwi et Yabuno was given. E. colony and E. crus-galli can be distinguished in some morphological characters, particularly with respect to panicles character, and these two wild species differ more or less in geographic distribution. E. utilis and E. frumentacea resemble to E. crus-galli and E. colona respectively in the characteristics of panicle. From the evidences mentioned above, it is assumed that E. utilis has arisen from the hexaploid varieties of E. crus-galli probably in the Far East, and E. frumentacea from E. colona in the tropics.
1. Somatic chromosomes were counted by the root squash in 15 genera, in which 97 species and varieties, and 40 hybrids are included. The hybrids are 14 kinds of genus combinations in the Oncidium alliance. 2. New numbers (2n) were added in species: 2n=24, 26, 30, 32, 37, 40, 60, 84, 133 and 168 (Tables 1-3). 3. The basic numbers of chromosomes in the Oncidium alliance may be 5 and 7. 4. Most of the hybrids studied showed the sum of their parents' chromosome numbers though some hybrids have not (Table 4). 5. The chromosome numbers found in the hybrids are as follows (Table 4): 2n=28, 32, 34, 40, 41, 42, 44, 49, 50, 56, 58, 59, 60, 61, 76, 80, 84 and 112. 6. Karyotypes could be analysed in some species and hybrids. Generally only constrictions can be seen, and trabants, seta, etc. can not easily be recognized.
Natural hybridization between Ae. sharonensis and Ae. longissima was found to occur in the Sharon Plain of Israel, but to be confined to disturbed habitats. Hybrid swarms were examined morphologically by means fo Anderson's technique of population sampling and were found to exhibit characteristic hybrid variation patterns. Since the species concerned differ in a reciprocal translocation, the hybrid nature of the populations investigated could be assessed from the presence of translocation heterozygotes. These observations have also been supplemented by an examination of artificial F1 and F2 hybrids.
Chromosomes were studied from five species and two unnamed plants of the genus Agapanthus. Karyotypes and ideograms were prepared, the chromosomes were grouped into classes of different size, and formulae were prepared for all the plants. The 2n number was found to be 32 in A. praecox and A. orientalis, 30 in A. campanulata, A. inapertus, A. minimus, and one of the unnamed plants, and 29 in the other unnamed plant. A. orientalis and one of the unnamed plants had two supernumerary chromosomes. The chromosomes of A. praecox and A. orientalis are not inconsistent with the position that these species are synonyms.
Freshly collected specimens of Bryum sp. (gametophyte) and Funaria hygrometrica (gametophtye and sporophyte) were used for the study of the fine structure and development of chloroplasts. The fully-developed chloro-plasts of both species are ellipsoidal. The chloroplasts are bounded by a well-defined dense membrane. The laminar systems within the chloroplasts have their double closed lamellae or discs arranged into stacks or grana. The stroma lamellae are merely extensions of grana discs which form some sort of a continuity between the grana. In general, the stacks of Funaria chloroplasts are more compact than those of Bryum. Osmiophilic globules occur in the chloroplasts of both species. The development of chloroplasts of both species may be summarized as follows: 1. In the proplastids, vesicles and osmiophilic globules cccur. 2. The lamellae are formed locally by fusion of the vesicles. 3. The number of lamellae increased with size of the chloroplasts, and the lamellae form closed double membranes or discs. 4. The discs become arranged into stacks which indicate grana formation. 5. Osmiophilic globules are present at all stages and show an increase in size with the advance of development.