116 



Dr. J. D. F. Gilchrist on the Fqqs and 



a modification. At this point it was about '04 mm. in dia- 

 moter, hut soon dimiuislicd to about 010 mm. The hhiment 

 appears to be homogeneous throughout, but, if treated with 

 hot caustic j)Otash, it has the appearance of a thick-walled 

 tui)e. 



At the distal pole of the egs:, opposite that from which 

 tlie filament arises^ there is a marked differentiation of the 

 surface of the egg, on a small terminal area about "2 mm. 

 in diameter. This area is covered with clear polygonal 

 markings, which vary in size, being large to\var(ls the 

 periphery, where they fade off into the surrounding surface. 

 Near the centre they become smaller and less distinct^ and 



Egg and filament of Nauo'ates dudor. 



pass into a small thickened ring, in the centre of which the 

 micropyle may be clearly seen. 



There is a large perivitelline space, about a fourth of the 

 diameter of the whole egg in breadth at the middle of the 

 egg. In the specimen figured this breadth was '32 ram. 



The egg i^roper or yolk is an ovoid mass, somewhat more 

 oblong in shape than the outer shell of the egg. It is clear, 

 but granular, and no traces of vesiculations nor oil-globules 

 "were seen. In preserved material several cases were ob- 

 served in which the yolk had shrunk away from its 

 surrounding perivitelline substance, and, in such cases, at 

 the distal eud opposite the micropyle, a small funnel-like 



