150 LARVA OF LIMULUS. 



the carapace. In this stage the six segments of the thorax 

 shine still more clearly through the chitinous covering, and in 

 a side view one gets a most perfect idea of the swimmerettes. 

 The animal remains, however, as far as its appendages are 

 concerned, in the Nauplius stage, and in this it remains as long 

 as it swims on the surface, for in the last stage, in which three 

 pairs of thoracic legs were visible on both sides of the mouth 

 under the larval skin, no abdominal feet had as yet disen- 

 gaged themselves. The animal has grown a little, its spine is 

 somewhat longer and more pointed, but it still must be con- 

 sidered as a larva. 



[It will be interesting to know precisely to what animal 

 Suhm's Philippine larva above described belongs. It differs 

 from all known Cirrhipede larvae in the structure of the tail. 

 There is no ground whatever for reviving the view, discarded 

 by Suhm himself, that this larva belongs to a Limulus. — 

 e'. R. L.] 



