88 THOS. H. MONTGOMERY jr., The Spermatogenesis in Pentatoma etc. 



Figs. 200 — 202. 1st spermatocytes, dyaster; in Fig. 202 the 

 chromosomes are not fused together, but lie so densely that they cannot 

 be clearly distinguished. 



Figs. 203 — 205. 2nd spermatocytes, lateral view of the spindle; 

 in Fig. 205 only half the spindle lies in the plane of the section. 



Fig. 206. 1st spermatocytes, dyaster, the centrosomes do not lie 

 in the plane of the section. 



Figs. 207 — 212. Pole views of the chromosomes in the daughter 

 cells (2nd spermatocytes) of the 1st spermatocytic dyaster. 



Figs. 213 — 215. 2nd spermatocytes, prophase of the monaster. 



Fig. 216. 2nd spermatocyte, monaster. 



Fig. 217. 2nd spermatocyte, commencement of metakinesis. 



Figs. 218, 219. 2nd spermatocytes, successive dyasters. 



Fig. 220. 2nd spermatocyte , pole view of one of the daughter 

 cells (spermatids) of the dyaster. 



Figs. 221 — 224. 2nd spermatocytes, final stages of the dyaster, 

 the daughter cells being the spermatids. 



Fig. 225. Tropicoris, transverse section through the middle of the 

 testicle; the large generation of cells occurs in the follicles numbered 

 1 and 3. (Zeiss, obj. A, oc. 2.) 



Fig. 226. Longitudinal section through the proximal end of one 

 follicle (the 4th) of the testicle of Pentatoma, to show the mode of 

 grouping of the spermatocysts. (Homog. immers. ^/i^, oc. 2.) 



Fig. 227. Longitudinal section through the mature testicle of 

 Pentatoma, the section nearly parallel to the flat side of the testicle. 

 The numbers denote the follicles, the cells of the large generation being 

 found in follicles 1 and 3. Sg. Z zone of the spermatogonia ; 6r. Z 

 growth zone of the spermatocytes ; J). Z zone of the reduction divisions ; 

 St. Z zone of the spermatids ; Sp2. Z zone of the spermatozoa. (Zeiss, 

 obj. A, oc. 2.) 



