Germ Cells of Leptinotarsa Signaticollis. 183 



a thin double spireme, which condition persists for quite a while. 

 Fig. 43 is a drawing of a nucleus considerably older, in which the 

 chromatin represented by the beaded strands is beginning to 

 lose its affinity for the stain. Thus Figs. 39 to 43 inclusive in the 

 female, present an interesting parallel to figs. 45 to 48 inclusive 

 in the male, and show that the stages marking the beginning of 

 the growth period are exactly the same in both sexes. 



The important point is the presence of a bi-partite nucleolus 

 in the resting stage of the ovocyte that bears a very striking 

 resemblance to the body found at a corresponding stage in the 

 spermatocyte. 



Stevens ('06) found in L .decemlineata (Doryphora deceinlineata) , 

 a closely related form, that the spermatogonial number is thirty- 

 six. The nucleolus of the resting stage is described as an unequal 

 pair, the members of which separate in the first division and divide 

 equationally in the second. The great similarity between the 

 telophases of the first division as represented by Stevens in Figs. 

 175 and 176 of her paper and the corresponding stage in signati- 

 collis led me to examine the ovaries and testes of decemlineata. 

 I found the nucleolus of the primary spermatocytes to accord 

 with Stevens 'description as far as the resting stage is concerned, 

 but that its unequal components separate in the first division 

 does not seem to be the case, and in this regard I cannot agree with 

 her observation. Figs. 62, 63, and 64 show various stages in the 

 first division, in which the behaviour of the accessory body is 

 exactly the same as in signaticollis. 



Stevens claims that the V-shaped body seen in the first sper- 

 matocyte spindles is the larger component of the unequal pair 

 and that owing to its smaller size the lesser component is often 

 concealed by the '^ V, " ''when the group has the appearance of an 

 Orthopteran accessory". 



In signaticollis there can not be the slightest doubt as to the 

 accessory not dividing in the first division, and since the two 

 species are so closely related (cf. Tower '06), some similarity in 

 the behavior of this body is to be expected. That Stevens should 

 have placed a different interpretation on this point is not strange 

 in view of the cytological difficulties in the way of a satisfactory 



JOURNAL OF MORPHOLOGY. — VOL. 21, NO. 2. 



