34 THOS. H. MONTGOMERY jr., 



described by Platner ('86) for other Insects. The cells of the large syn- 

 cytia differ from the usual type of cells only in their greater amount of 

 cytoplasm and yolk, while the volume of the nucleus and the chromatin 

 is the same in both; hence they do not constitute a special generation 

 of cells. There are no facts to show that these syncytia represent 

 masses of pathologically changed cells. Here and there in the testicle 

 may be seen degenerating cells, but they are far less numerous than 

 the cells of the syncytia; while if the cells of the syncytia represented 

 the commencement of degeneration changes, later stages of degenerated 

 cells should be found in greater abundance. The degenerating cells 

 (Fig. 94) are characterised by the dense, homogeneous appearance of 

 the cytoplasm, and the absence of a nuclear membrane ; large, rounded 

 masses of chromatin lie either wholly in the nucleus, or scattered 

 irregularly throughout the cell; the cell membrane is retained. 



The syncytia thus appear to consist of cells which have been 

 more richly nourished than the others, but which develop normally in 

 every respect. They do not represent a particular stage in the growth 

 period of the spermatocytes, since appearances would show that prob- 

 ably not more than about one-third of the total number of spermato- 

 cytes become grouped into such masses. It might be supposed 

 that they are destined to give rise to a particular kind of spermatozoa, 

 by virtue of their large amount of cytoplasm; but this view is not 

 very probable, since when the syncytia in the rest stage segment 

 into separate cells, or into small groups of two or three cells each, 

 the cytoplasm of each of the latter is found to be little if any greater 

 in amount than in the isolated cells. The syncytia occurred in all the 

 follicles of the testicles of Pentatoma examined ; it is quite likely that 

 their number or size might vary at different seasons of the year, or 

 even according to the state of nutrition of the individual Insect. 

 Perhaps their absence in the two testicles of Tropicoris examined 

 might be due to some such cause. Aberrant cell structures, charac- 

 teristic for particular seasons of the year have been described for the 

 spermatogenesis of other animals, such as the spermatogonia with 

 polymorphic nuclei in Salamandra (according to Meves, Vom Rath 

 and others), and which I have found in testicles of our common 

 American Plethodon cinereus. Meves regards such cells as typical 

 for the Fall and Winter, which in the Spring become changed to the 

 normal type of cells; while Vom Rath believes them to be states of 

 degeneration produced by an insufficiency in the supply of nourishment 

 during the Fall and Winter, basing his opinion in part on the study 



