. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. THE SPERMATOGENESIS OF THE MYRIAPODS. 2O5 As will be seen from the foregoing description, the tetrads occurring in Scolopendra are similar to those previously described by other authors in various arthropods. What may be taken as the type of these figures was first reported by Paulmier, '99, in Hemiptera and McClung, 'oo and '02, in Orthoptera. Structures differing slightly in detail, the apparent divergence evidently being due more to interpretation than to any essential morpho- logical variations, have been found in other
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. THE SPERMATOGENESIS OF THE MYRIAPODS. 2O5 As will be seen from the foregoing description, the tetrads occurring in Scolopendra are similar to those previously described by other authors in various arthropods. What may be taken as the type of these figures was first reported by Paulmier, '99, in Hemiptera and McClung, 'oo and '02, in Orthoptera. Structures differing slightly in detail, the apparent divergence evidently being due more to interpretation than to any essential morpho- logical variations, have been found in other arthropods by Henk- ing, '91 (Pyrrhocoris), Vom Rath, '95, '97 (Gryllotalpd), Toyama,. FIG. 15. X i,44O dia. Nucleus of first spermatocyte during late prophase, show- ing various modifications in the shape of the chromosomes at this time. The acces- sory chromosome is seen to be split longitudinally. Centrosomes with well-developed astral rays at opposite poles of the nucleus. '94 (silkworm), Riickert, '95 (Copepoda), Montgomery,1 '98, 'oo, 'oi (Hemiptera, Pcripatus], Blackman, 'oi (Scolopcndni), P. Bouin, '02 (Lithobius), Miss Nichols, '02 (Oniscus], and others. In the tetrads observed by all of these authors, the cleavages universally represent a longitudinal and a transverse division of the double or bivalent chromosome of the spermatocyte. Apparent discrep- ancies are undoubtedly due to mere variations in detail or differ- ences in interpretation and denote no real important divergence in the formation of the tetrads. 1 In his earlier paper Montgomery reported two cross divisions as occurring in Pentatoma (£ut-/n's/us), but in his subsequent publications has denied the accuracy of this observation and now believes that one longitudinal division invariably Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the origina
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
