EXPLANATION OF PLATES, III — IV. 



Fig. 30. Chromatin bodies represented in last figure are now collected at centre 

 of nucleus. Single nucleolus is seen in centre of these chromatin bodies, 

 (ditto). 



Fig. 31. Nucleus in which chromatin granules again separate from one another 

 and show appearance of normal resting nucleus. Large nucleolus consist- 

 ing of small chromatin granules is seen, (ditto). 



Figs. 32-43. Sperm-mother-cells nearly in same stage of development, (v) " Ver- 

 bindungsbrucken " ; (c) extruded nucleolus; (e) nucleus of cyste. In fig. 

 40 collection of cytomicrosomes (b) is shown. (Same magnification as 

 above.) 



Fig. 44. More advanced stage. Chromosomes show ring-like form. (Zeiss, homog. 

 imm. 1/12, Oc. 4). 



Fig. 45. Similar stage as above. Each ring broken up into four chromosomes. 

 (Same magnification as above.) 



Figs. 46-53. Various stages of first division of sperm-mother-cells. Figs. 46-48 re- 

 present early stages of division, showing attraction-spheres, oblique 

 spindle and " Verbindungsbrucken " (v) ; and in fig. 49 polar and central 

 spindles are seen. Stained with Bohmer's haematoxylin. (Zeiss, 1/12, 

 Oc. 4). Figs. 50, 50', 51, 52, spindle stage. Fig. 53 diaster stage of 

 the same. Treated with Hermann's triple staining. (Zeiss, '/u, Oc. 5 

 except fig. 50' which is drawn by Zeiss. i/i 2 , Oc. 5.) 



Fig.?. 54-60. Second division of sperm-mother-cells, immediately following last divi- 

 sion. Figs. 54 and 55, spindle stage. (Zeiss, homog. imm. 1/12, Oc. 5). 

 Fig. 56, diaster stage of same. (Zeiss, homog. imm. 1/12, Oc. 4). Fig. 

 57 shows polar view of diaster stage. (Zeiss, Obj. 1/12, Oc. 5). Fig. 

 58, side viw of same. (Magnif. as above). Fig. 59, little more advanc- 

 ed stage. Central and polar spindles have separated from each other, 

 (magnified as above). Fig. 60, mDre advanced stage of same, showing 

 two cell-plates; (k) nucleus. (Zeiss, Obj. 1/12, Oc. 4). Those shown 

 in figs. 54, 55, 56 stained with Hermann's triple staining while rest are 

 treated with Bohmer's haematoxylin. 



Figs. 61-83. Various stages of metamorphosis of sperm-daughter-cells. Figs. 61, 

 62, a, b show sperm-daughter-cells with remnant of spindle fibre and 

 collected mirosomes (in). (Zeiss, Obj. ijn, Oc. 4. and 5). Stained with 

 Bohmer's haematoxylin. Fig. 62 c, d represent mire advanced stage of 

 the same, showing " Nebsnkern " («). Treated and magnified as above. 

 In figs. 63 and 64, cell-body is little elongated to form tail of sperma- 

 tozoon ; (k) nucleus («) " Nebjnkern " (m) mitosome are shown. Acetic 

 acid methyl green preparation and magnified by Zeiss, Obj. J, Oc. 4. 

 Figs. 65-78, 74-76, 78-81 show head and " Nebsnkern," of spermatozoa 

 showing successive stages of metamorphosis. (K) nucleus, (») " Neben- 

 kern," (m) mitosome. Bohmer's hasmatoxylin except fig. 72 which is 

 stained with acid fuchsin ani methylen blue. Magnified by Zeiss, 

 homog. imm. i/u, Oc. 5. except figs. 67, 69, 72, 74, 75 which are drawn 

 with Zeiss, homog. imm. 1/12, Oc. 4. Fig. 81 shows head of nearly 

 mature spermatozoon, killed with picro-acetic acid and stained with 

 picro-carmine. Fig. 82 represents cyste containing nearly matured 

 spermatozoa. At right end of figure large supporting cell is shown. 

 Treated as above. Zeiss, homog. imm. 1/12, Oc. 3. Fig. 83 shows 



