clGScriptions of it. In lhj second place, by tlie study of 

 young stages, I liave been able to trace the transformation 

 of the typicv.l Lamollibranch larva into the highly spe- 

 cialized "Ship-v.'orm". 



I have also traced the early embryology on the arti- 

 ficially fertilized eggs of X. fimbriata and T. norvegica, 

 in both of v;hich the eggs are laid free into the water. 

 Stages later than the typical Lamellibranch veliger raised 

 in aquaria, I have not been able to observe. The interme- 

 diate stages, betvTeen these and the newly-attached larva, 

 I hope to observe on the larvae of some viviparous species 

 at a fixture tine, so as to complete my study of the devel- 

 opment from the egg to the sdult. 



