ORTHOPTERAN SPERMATOGENESIS 679 



and it is most unlike that of the first spermatocyte. In the size 

 and form of the spindle and shape of the chromosomes it most 

 resembles the spennatogonial mitotic figure, but differs in the 

 possession of the haploid instead of diploid number of chromo- 

 somes. While it is like the first spermatocyte in number of chro- 

 mosomes it is most unlike in the form of the chromosomes and 

 spindle. "WTien viewed from the pole the second spermatocyte 

 metaphase figure shows all the elements of like form — simple 

 rods with terminal fiber attachment and arranged radially in 

 the equatorial plate (figs. 12, 13, 16 to 19, 31, 47, 49, 50, 53 to 58). 

 A lateral view reveals each chromosome as two rods superimposed 

 with the inner ends, where the fibers attach, in close contact, 

 while the outer ends may be widely divergent (figs. 48, 51 and 52). 

 Occasionally chromosomes lying in the center of the group may 

 swing widely apart, remaining united only at the point of fiber 

 attachment and may then appear abnost as straight rods. Such 

 instances are represented in figures 18, 49, 50, 53, 55, 57 and 95. 

 In the cases of Stenobothrus, Chorthippus, Chloealtis and Tri- 

 merotropis, where some of the chromosomes have median and 

 subterminal fiber attachment in the spermatogonia, a similar 

 series of such chromosomes reappears in the second spennatocytes. 

 Under these conditions polar views of the second spermatocyte 

 metaphase (figs. 68 to 76) instead of presenting all the chromosomes 

 as simple rods will show V's with equal or with unequal arms, de- 

 pending upon the point of fiber attachment. Divergence of the 

 outer ends also occurs to some extent in such chromosomes. 



DISCUSSION OF RESULTS ON THE SPERMATOCYTES 



In weighing the evidence presented in the different accounts of 

 Orthopteran maturation phenomena it will be necessary to take into 

 consideration the following items; (1) the relation of the chromo- 

 somes of the first spermatocyte to those of the spermatogonium, 

 (2) the composition and form of this first spermatocyte chromo- 

 somes, (3) the relation of the chromosomes of the first sperma- 

 tocyte metaphase to those of the prophase, (4) the position of 

 the chromosomes in the spindle, noting the Hippiscus type and 



