6578 



Annelides. 



Fig, 6. — Carapace of the 

 Masked Crab, to which eyes 

 have been painted in. 



places ; a little observation showed their track in the scratches that 

 their feet had made, and where these ceased the animal was sure to 

 be some six or ten inches below the surface. Another burrower is 

 the masked crab (Corystes Cassivilaunus) so 

 named from the imprint of the human face being 

 distinctly marked upon its back. I took one 

 once and kept it for some time to the amusement 

 of many, so striking was the resemblance to the 

 portraits of Mr. Pecksniff; and I only regretted 

 that the animal already had received a name, 

 and that I could not associate it with that 

 eminent sneak. 



These are active creatures, all of them, and 

 much too nimble to allow weeds and animals 

 to fix an abode and grow upon their sur- 

 faces. Then is it unreasonable for us to assume that, coupling their 

 active character and general intelligence with the previously recog- 

 nised statement that in their growth they pass through the triangular 

 form, they stand as animals higher in their class than their more slug- 

 gish congeners, the spider-crabs. In the study of the lower forms 

 we may make use of our own experience in the human tempera- 

 ment. The most perfectly developed nervous system is also the most 

 active in its muscular action. 



It is but just, since the triangular crabs have been recognised by 

 the leading carcinologists as the highest of the class, that the 

 reasons on which their opinions are based should be clearly under- 

 stood, since they rest strictly upon anatomical evidence. It is on the 

 fact of the consolidation of the nervous ganglia into a mass, and 

 which, therefore, has been considered by carcinologists in general, 

 and Professor Dana in particular, to be an increase of nervous power, 

 and to approach the animal nearer to those which possess a true 

 brain ; to use his own words, " a centralization of the nervous ganglia 

 is a true cephalization." 



(To be continued.) 



Remarkable Earth-worm. — I shall be very glad if some reader of the 'Zoologist' 

 can assist me with information in the following matter. How many species of earth- 

 worm (Fumbricns) have we in Britain? and have we one species whose movements 



