214 SEA-SIDE STUDIES. 



The microscope reveals fresli wonders, the head being 

 furnished with crab-like nippers ; the alimentary tube, 

 instead of occupying an isolated and dignified j)Osition 

 in the body, meanders out into each of the legs, so that 

 the leg repeats the body in its internal structure, as well 

 as in aspect. This ramified alimentary canal is covered 

 with brownish yellow globules or cells, called ''hepatic 

 cells," and supposed to represent a rudimentary liver, 

 Mr Gosse, in his pleasant book on Tew 6^/, mistakes this 

 intestine for the circulating system ; but the animal has 

 710 circulating system whatever. " Each of the long 

 and many-jointed limbs is perforated by a central ves- 

 sel," he says, " the walls of which contract periodically 

 wdth a pulsation exactly resembling that of a heart, by 

 which granides or pellucid corpuscles of some sort or 

 other are forced forward/' It was food which Mr 

 Gosse saw thus moved ; the blood-circulation, such as 

 it is, he correctly saw in what he describes as the extra- 

 vascular circulation ; only we should add, that vascu- 

 lar circulation there is none. The blood, if blood it 

 can be called, is outside the intestine, bathing the walls 

 of the body, and moved to and fro by the peristaltic 

 action of the intestine. Curious as this Nymphon 

 gracile is, I had reason to be the more pleased at find- 

 ing one, because while the latest authorities declare 

 nothing to be known of the development of the Pycno- 

 gonidce, I had been fortunate enough, at Ilfracombe, to 

 discover some of the embryonic phases, of which I made 

 drawings, and awaited further opportunity for pm-suing 

 the subject. 



