No. I.] SPERMATOGENESIS OF BATRACHOSEPS. lOI 



Figs. 4 and 5 represent two successive sections of one polymorphous sper- 

 matogonium in the resting stage. The nucleus is more contracted, with fewer 

 folds. Two linoplasts. The chromioles are being drawn into the leaders and 

 united into chromomeres. The spheres are being reconstituted, the granular 

 zone being the granosphere. An archosome is seen in Fig. 5. 



Figs. 6 and 7. Two detail figures of polymorphous spermatogonia with fully 

 reconstituted spheres, each with centrosomes. The nuclei are more advanced 

 than in Figs. 4 and 5. In Fig. 7 are seen several accessory archosomes, each 

 surrounded by a centrosphere. In each cell is a large linoplast. The nuclear 

 network is merely sketched in and not carried out in detail. 



Fig. 8. A large polymorphous spermatogonium in a more advanced stage of 

 development, in the imperfect resting stage. The nucleus has changed from poly- 

 morphous to globular. The largest dark body is the chromoplast, the smaller 

 one is probably a linoplast. Many distinct leaders have been formed, and are 

 now connected by a network of chromioles and chromomeres. The spheres have 

 been almost perfectly reconstituted, consisting now of an inner granosphere and 

 an outer plasmosphere, an archosome with two centrioles, and several accessory 

 archosomes, the latter scattered in the cytoplasm. 



Fig. 9. A large polymorphous spermatogonium, but in which the nucleus has 

 lost its folded or polymorphous nature, being now at the end of the resting stage 

 and just entering the prophases of mitosis. Between this cell and the one figured 

 in 10 there is not only a whole somatic mitosis, but at least three or four genera- 

 tions of round nucleated spermatogonia, all dividing by somatic mitosis, and with 

 twenty-four chromosomes each. The last of these generations gives rise to smaller 

 oblong cells, which pass through a stage of growth and then constitute the first 

 or imperfect resting stage of the auxocytes. In Fig. 9 there is seen a large lino- 

 plast, three chromoplasts, with endochromatic granules. Leaders are seen to 

 emanate from the chromoplasts. The spheres are not quite reconstituted. In the 

 center is an archosome with two centrioles. Several accessory archosomes in the 

 cytoplasm. The plasmosphere is starlike, the granosphere rounded and cup-shaped. 



Auxocytes : SperiJiatogonia with Round Nticlejis, Heterotypic Mitosis, and Twelve 

 Chromosomes {Tigs. 10-61). 



Fig. 10. Auxocyte in the imperfect resting stage. Three darkly stained chro- 

 moplasts with endochromatic granules. Leaders are centering towards the 

 chromoplasts and connected with them. The spheres are reconstituted. The 

 granosphere is cup-shaped ; the plasmosphere is indistinct and hardly to be defined 

 from the cytoplasm. An archosome with two centrioles at the outer edge of the 

 granosphere ; several accessory archosomes in the plasmosphere, all being con- 

 nected by a thread and by rings of somosphere. The darker granules in the 

 nucleus are chromomeres, containing each from one to three chromioles. Only a 

 small part of the nuclear contents is sketched. 



Fig. II. Auxocyte in the imperfect resting stage more advanced than the last 

 figure. Two chromoplasts. The spheres are reconstituted, the inner one 

 stained red being the granosphere. In its center is an archosome with two 

 centrioles. Numerous accessory archosomes in the cytoplasm, some of them 

 connected by threads of somosphere. The detail figure alongside shows the chro- 

 matin network, each chromomere consisting of several chromioles. The leaders 

 are projecting from the chromoplasts. 



