170 CARRIE I. WOOLSEY. 



readily as the V, however, since their union is evidently not 

 permanent and the rods separate in the later growth stages. 

 The fact that they are associated in the early stage forming two 

 sets of related rods on the periphery strengthens my belief in 

 the manner of the V-formation in the other forms. In the place 

 of these two sets of rods, or of the one V and one set of rods in 

 No. 503, I found two V's in No. 560 a representative of /. 

 unicolor. Here we find the same thing taking place as in the 

 one V type. In the place of a long V formed by the short V 

 and the rod mates in the spermatocyte figures, we here find a 

 ring formed by an end-to-end union of the arms of the V's 

 (Figs. 65-67). 



It will be seen that throughout the three species of this genus 

 of Jamaican LocustidcB the number of chromosomes, 35 remains 

 constant, although their behavior varies not only within the 

 genus but even within the species. In seven of the ten indi- 

 viduals studied representing three species, there are 35 chromo- 

 somes of the simple rod type. As a whole, the division figures 

 are clear and distinct and the growth stages can be followed 

 with moderate certainty. In the first spermatocyte, the acces- 

 sory passes undivided to the one pole making the number in the 

 two daughter cells 18 and 17 respectively. When these divide 

 in the second spermatocyte, division takes place longitudinally 

 and the spermatids number 18, 18, 17 and 17 respectively, the 

 last two being without the accessory chromosome. These then 

 will produce males when fused with eggs, and the oosperm will 

 contain thirty-four autosomes plus the one sex chromosome 

 brought in by the egg. Those spermatids with eighteen, will 

 produce females, since here there will be two sex chromosomes, 

 one from the sperm and one from the egg in addition to the 

 thirty-four autosomes, making the number 36 in the females. 



I find, however, an exception from this general rule of 35 

 separate rod type chromosomes in each species studied. J. flava 

 shows in one individual the presence of two pairs of associated 

 rods in all spermatogonial figures. The rods that make up each 

 pair or set are unequal and hence can not be mates. In number- 

 ing the members of the complex these rank as 16 and 14 in the 

 graded series, 18 being the unpaired accessory and the largest 



