Chap, i.] 



CRABS. 



trees with the greatest ease. A white Sand-crab {Ocypoda), 

 burrows deep in the sand-hills, and is very difficult to dig out, 

 and a huge ugly Land-crab {Cardisoma) is common further 

 inland. A small White-crab {Remipes) lives in the sand on 

 the shore just below the verge of the water ; it burrows rapidly 

 in the sand until covered, and then by ejecting a small jet of 

 water from its gills clears a small passage for respiration, 

 remaining concealed. 



LAND NEMERTINE, TETRASTEMMA AGRICOLA. (yOUNG MALE.) 



Pt. I — 4 Successive portions oi the proboscis ; i entrance ; 2 papillary 

 portion ; 3 pouch of stylets ; 4 glandular portion ; ca muscular entrance 

 of glandular portion ; o mouth ; i intestine ; g ganglion ; n lateral 

 nerves. 



(After a figure by Von Willemoes Suhm.) 



A land Nemertine worm was discovered by Von Willemoes 

 Suhm, living in moist earth. Only one other terrestrial Nemer- 



