508 D. H. WENRICH 



represents an entire chromosome. These structures will be con- 

 sidered here only as further evidences of the exact organization 

 of each chromosome. 



As pointed out in the observations, these chromomere-vesicles 

 are attached to the chromomeres at the apices of the V's in 

 Chorthippus — quite regularly in chromosome number 9, less so 

 in numbers 7 and 8 — and near one end of the telomitic chromo- 

 somes 4 and 8 in Trimerotropis. In Chorthippus one is practi- 

 cally always attached to the accessory. 



The relationship of the vesicle to a particular part of this 

 accessory is not readily observable in the growth period, as 

 shown in figures 1 to 6, plate 3, but on plate 1, it is readily seen 

 that the vesicle (c) is attached to a point near the middle but 

 always nearer one end than the other, indicating that in this 

 case, also, the relationship is to some definite region or chromo- 

 mere of the accessory. 



Whenever the chromomeres at the apices of the V's in Chor- 

 thippus can be distinguished in the same tetrad which shows 

 a vesicle, it is found that the vesicle is always attached to that 

 one of the pair of chromomeres which belongs to the longer 

 arm of the V. This is seen especially on plate 3 in figure 9 

 from the smear and in figures 12 to 14 from sections. It is also 

 seen in in chromosomes 8 and 9, cell A, plate 1. 



Similarly, in Trimerotropis, the relationship of the granular 

 appendage is constant in the two chromosomes to which they 

 are attached. In plate 2 the relationships are not so definitely 

 ascertainable, because of the more condensed condition of the 

 chromosomes and of the granules in the cluster, but it is notice- 

 able that the cluster is closer to the end in chromosome 8 than 

 it is in chromosome 4. This is better seen in figures 22 and 23 

 in plate 3. In both cells the clusters are attached to chromo- 

 some 8 at or near the last chromomere but one, near the end 

 and in chromosome 4 to the fourth chromomere from the end. 

 In figure 23 the ends of chromosomes 4 and 8 are in contact. 

 The two appendages are also in contact, but it could not be defi- 

 nitely determined whether or not they had fused together. 

 Taken all in all, this brief study of these slightly-understood, 



