8 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



Plate I. Figs. 7, 19 (see Explanation of Figures), Plate V. Figs. 204, 

 210, 211). This mass may be slightly vacuolated and may show nu- 

 cleoli. Some stages of degeneration in the testes of Caloptenus are 

 shown in Plate V. Figs. 202-220. The nucleus may divide amitotically 

 once, twice, or three times (Figs. 206, 212, 214, 215). This may result 

 in ragged granules or strands, or in regular chromatic spheroids (Figs. 

 205, 207, 220). It is evident from Figures 202-220, since all are 

 drawn to the same magnification, that some degenerating cells increase 

 enormously in size. These degenerating cells are very numerous in 

 Cicada and Caloptenus, especially in the latter. 



In Cicada there are frequently seen spermatozoa and various stages 

 in the metamorphosis of spermatids which are four or five times as large 

 as the corresponding normal forms ; they may be called giant spermato- 

 zoa. Normal spermatids are represented in Plate I. Figs. 2, 3, 4, 9. 

 Stages in the metamorphosis of giant spermatozoa, drawn to the same 

 magnification, are shown in Figures 12, 13, 21, 22. Figures 78-103 

 (Plate II.) represent giant spermatid cells found accompanying normal 

 cells. Figure 104 shows normal spermatids, the magnification being 

 the same as in Figures 78-103. The striking similarity between the 

 corresponding stages of a normal spermatid and giant forms is very 

 readily seen on comparing Figures 62-77 with Figures 78-86. The 

 first series is much more highly magnified than the second, hence the 

 apparent equality of size. 



Figures 202, 203 (Plate V.) represent the only examples found in 

 Caloptenus which resemble the giant spermatozoa of Cicada. 



What is the meaning of giant spermatozoa 1 Frenzel ('91, '91°), Lowit 

 ('91), vom Rath ('90, '91, '93), Verson ('91), Ziegler ('91), Ziegler und 

 vom Rath ('91), Flemming ('89), Geberg ('91), and Meves ('91), have 

 discussed the question of amitotic division, Lochkerne, Ringkerne, and 

 other degeneration conditions. I believe with vom Rath ('93), that 

 " Alle Zellen welche einmal amitotische Kernteilung erfahren haben, 

 konnen sich unter keiner Bedingung mehr mitotisch teilen, sie gehen 

 vielmehr einem sicheren Untergang entgegen." I believe that the 

 giant spermatozoa are not functional, that they are excluded from the 

 developmental series and really come to naught. But they arise in 

 Cicada directly from spermatogonia without cell division, by a meta- 

 morphosisis of the nucleus, which may or may not be accompanied by 

 amitotic division of the nucleus. In such spermatogonia the nuclei may 

 divide amitotically two or more times (Fig. 8). Then, in the majority 

 of cases, the chromatin breaks up into numerous fragments, which are 



