598 L. H. OOUGH. 



After having cut it I foiuid it to contain about eight 

 nuclei ; these were all situated near each other, not far from 

 the surface. The rest of the egg consists of yolk, the whole 

 being surrouiided by a delicate inner membrane. 



The position of the nuclei in a group near each other, under 

 the surface, makes it seem probable that the fertilisation of 

 the egg took place in the middle of the egg, and that the 

 first cleavages took place there too ; the cells resulting from 

 these cleavages then wandering towards the surface, just as 

 they do in spiders. The pressure of the two membranes 

 also points to a resemblance with most of the other orders 

 of Arachnids, whose eggs are also regularly enclosed in two 

 membranes. 



The yolk itself consists of at least two different kinds of 

 yolk elements. The first of these tinges very freely Avith 

 eosin, and is not influenced by haematoxylin. It consists of 

 larger and smaller spherules measuring between "09 mm. 

 and *02 mm. ; they form the greater bulk of the yolk. The 

 other yolk element is much more irregular in shape, and 

 helps to fill the spaces between the spherules of the element 

 first described, to which it adheres, thus becoming crescent- 

 shaped in cuts, and in realit}^ forming convex-concave lenses. 

 It also differs in tinction from the first described kind of 

 yolk, staining both with liPGinatoxylin and eosin to a light 

 purple. 



The size of these yolk-bodies varies between 'OoG mm. and 

 •05 mm. The distribution of the yolk elements does not 

 seem to follow any definite rule, unless, perhnps, that the 

 yolk elements last described are more numerous in the 

 interior of the egg. I shall not again refer to the yolk or 

 to the membranes, excepting where I have to point out a 

 change in them. 



Stage II. 



The next stage at my disposal is only a little further 

 developed thnn the one just described. It is derived from 



