428 



A. E. Verrill Decapod Crustacea <*f 



The antennules are small, folding vertically, the tips reaching but 

 little beyond the eyes. Antenna' -mall, about as Ion-- as tin- eye- 

 stalks. Outer maxillipeds have the menis sliort ami broad, with a 



decided notch on the inner distal edge, at the articulati 1' palpus. 



The ischium is broader than long, with a rounded or semicircular 

 lobe on its inner margin; exognath is Miiall ami short. The large 

 palpi occupy about all the space to the liases ,,f the antennul< -. 

 The anterior lobe of the sternum separates the liases ,,(' d,,. max- 

 illipeds. Legs and maxillipeds very hairy. 



The abdomen is convex and has the rings thin, hut somewhat 

 indurated above. In the female the e<li;cs are expanded and form a 

 well developed egg-pouch below, containing eggs in two specimen^. 



Figure 48. 7V<>;//or<i /</, MIS <-,-ulH<-nl,i, . . anterior parts, from beln\v : diagram- 

 matic sketch, nnicli enlarged, from a Domiuira s 



This curious species lives in oven-shaped cavities or dens formed 

 in the upper surface of living corals, especially of J/V.X-.XY/, M<je.<tmlr<i, 

 Dichocomia, etc.; as many as s-iu' such cavities are sometimes found 

 in a coral six inches in diameter. The opening of the den is usually 

 semicircular or lunate, commonly oblique to the surface of the coral; 

 the opening being preserved, no doubt, by the friction due to the 

 constant motions of the crab. The downturned, rough, and dirt- 

 covered front of the crab serves as a lid or operciilum, closing the 

 aperture very nicely. The crabs can leave their dens, at least when 

 young, as they often do so when the fresh corals are put aside to dry. 

 The full grown crabs are probably unable to leave their dens.* 



Length of carapace in one of the larger females, 7 mm ; breadth, 

 4 mm . This one carries eggs. 



It does not appear to be common at Bermuda. Abundant at 

 Dominica I., in Jlitssa and JLwnidra clivosa, from 3-5 fathoms 

 (A. H. V., 1906, Yale Mus.). 



* In the figure pi. xxviii, fig. 8, the crab was intentionally placed in a den too 

 large for it, in order to show its form. 



