202 SEA-SIDE STUDIES. 



descry two specimens of marine spiders, or daddy-long-legs 

 {Nymphon gracile), very curious to behold. They have no 

 body to speak of ; a mere line, not thicker than one of their 

 legs, representing the torso. Tie a piece of silk thread, about 

 one-fourth of an inch long, into four equidistant knots, and 

 that will represent the body ; from each of these knots let 

 much longer pieces of the same thread dangle, and you have 

 the legs ; split the tip of the thread into three filaments, and 

 you have the head ; gum bits of dirty wool, about as large as 

 a pin's head, on the second legs, and you have the egg-sacs : 

 and with this the animal is complete. The microscope re- 

 veals fresh wonders, the head being furnished with crab-like 

 nippers ; the alimentary tube, instead of occupying an iso- 

 lated and dignified position in the body, meanders out into 

 each of the legs, so that the leg repeats the body in its in- 

 ternal structure, as well as in aspect. This ramified alimen- 

 tary canal is covered with brownish yellow globules or cells, 

 called " hepatic cells," upon no very convincing evidence, 

 and supposed to represent a rudimentary liver. Mr Gosse, 

 in his pleasant book on Tenby, mistakes this intestine for the 

 circulating system ; but the animal has no circulating sys- 

 tem whatever. " Each of the long and many-jointed limljs is 

 perforated by a central vessel," he says, " the walls of which 

 contract periodically with a pulsation exactly resembling that 

 of a heart, by which granules or pellucid corpuscles of some 

 sort or other are forced forward." It was /oocZ which Mr 

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

 he correctly saw in what he describes as the extra-yascvd&T 

 circulation ; only wc should add, that vascular circulation 



