DEVELOPMENT OF ELASMOBRANCH FISHES, 17 



junction of the two cones. In one case of this kind I fancied 

 I could see (and have represented) a coloured circular body 

 in each cone. I do not feel any confidence that these two bodies 

 are constantly present; and even where visible they are very 

 indistinct. 



Instead of an ordinary nucleus a very indistinctly marked 

 vesicular body sometimes appears in a segment ; but whether 

 it is to be looked on as a nucleus not satisfactorily stained, 

 or as a nucleus in the act of being formed, I cannot decide. 



With reference to the situation of the cone-hke bodies I have 

 described I have made an observation which appears to me 

 to be of some interest. I find that bodies of this kind are 

 found in the yolk completely outside the germinal disc. I have 

 made this observation, in at least two cases which admitted of 

 no doubt (vide Fig. 7 nx). 



We have therefore the remarkable fact, that whatever 

 connection these bodies may have with cell-division, they can 

 occur in cases where this is altogether out of the question and 

 where an increase in the number of nuclei can be their only 

 product. 



These are the main facts which I have been able to de- 

 termine with reference to the nuclei of this stage; but it will 

 conduce to clearness if I now finish wdiat I have to say upon 

 this subject. 



At a still later stage of segmentation the same peculiar 

 bodies are to be seen as during the stage just described, but 

 they are rarer; and, in addition to them, other bodies are to be 

 seen of a character intermediate between ordinary nuclei and 

 the former bodies. 



Three such are represented in PL ii. figs. Sa, 8b, 8c. In all 

 of these there can be traced out the two cones, which are however 

 very irregular. The striation of the cones is still present, but 

 is not nearly so clear as it was in the earlier stage. 



In addition to this, there are numerous deeply stained 

 granules scattered about the two figures which resemble exactly 

 the granules of typical nuclei. 



All these bodies occupy the place of an ordinary nucleus, 

 they stain like an ordinary nucleus and are as sharply defined 

 as an ordinary nucleus. 



