IO6 MARGARET REED LEWIS AND WM. REES B. ROBERTSON. 



The number and also the characteristics of the chromosomes 

 observed in the living cells correspond with what was found in 

 the fixed preparations. In the first spermatocyte the chromo- 

 somes were as follows: Five "short rod" tetrads, three large 

 "compound ring" tetrads, derived from the three pair of com- 

 pound V chromosomes of the spermatogonium and the rod-like 

 sex chromosomes. In this genus, Chorthippus formerly known 

 as stenobothrus, there is a peculiar compounding of six pairs of 

 rod chromosomes to form the three pairs of V's that are charac- 

 teristic so far as is known of all the species of the genus (Meek, 

 'n, '12; Gerard, '09; Davis, '08). 



This peculiar process by which the three pairs of compound V 

 chromosomes are formed was first observed by Robertson (in 

 press). The subsequent behavior of these compound chromo- 

 somes was the same in the living cell as has been described from 

 the fixed preparations and the five rods, three V's and the sex 

 chromosomes (present only in one of the two daughter cells, 

 which result from the first spermatocyte division) were easily 

 identified in the second spermatocytes and in the spermatids. 



The Apical Cell. The apical cell lies in the blind tip of the 

 follicle surrounded by primary spermatogonial cells (Figs. 1,3). 

 It is a round cell, which contains a more or less oval nucleus, and 

 is attached to the walls of the follicle by several thick cell proc- 

 esses. The apical cell contains both mitochondria and neutral 

 red granules (Figs. I and 3). The former are fewer in number 

 than the latter and uniformly small in size (Fig. 3). They are 

 arranged as granular threads mostly in a layer around the nucleus. 

 The neutral red granules are considerably larger than the mito- 

 chondria and are scattered throughout the cytoplasm and in the 

 cell processes. When a preparation is stained with neutral red, 

 these granules in the apical cell and also in all of its processes 

 rapidly take up the stain, so that the apical cell becomes quite 

 red in appearance. While the few granules in the spermatogonia 

 which surround the apical cell take up the stain only after a 

 long time and then only in a few scattered granules so that the 

 spermatogonia appear practically colorless. The somatic cells 

 (Fig. i), which form the wall of the follicle, have abundant neutral 

 red granules and these stain with neutral red in much the same 



