NOTHRDS INVENDSTUS. 501 



A species constituting one of the group which closely 

 resemble N. horridus. It may be distinguished from 

 the other members of that group by the convex posterior 

 margin of its abdomen, its shorter legs, shorter apo- 

 physes on the rostrum, &c. 



Colour. — I have not ever seen this species in life, 

 but from the preparations I should presume it to be 

 brown, of medium depth. I am informed by the dis- 

 coverer (Mr. Bostock) that the creatures were not 

 covered with dirt. 



Texture rough and dull ; the creature is covered 

 with short villous processes of the cuticle, which are 

 easily rubbed off but when m situ give a granular 

 appearance ; they are not so large nor so well marked 

 as the similar processes in N. horridus, &c. 



Cephalothorax narrower than the abdomen, but not 

 conspicuously so. Rostrum small, conical, slightly 

 truncated. Gense very distinct. Rostral hairs almost 

 straight. Behind the rostrum the cephalothorax 

 widens and rises, forming a transverse edge some- 

 what bowed forward ; after a short distance it narrows 

 again suddenly, being deeply excavated for the inser- 

 tion of the first pair of legs. From immediately behind 

 the before-named transverse edge spring two chitinous 

 apophyses, bulbous at the proximal end, and having 

 very short cylindrical distal ends, very much shorter 

 than those of N. horridus, &c. ; they do not come near the 

 tip of the rostrum ; each of these apophyses bears a 

 thick hair closely set with short villous processes. These 

 hairs usually touch or cross. Pseudo-stigmata very pro- 

 jecting. Pseudo-stigmatic organs very short, with thin 

 peduncles and small, almost globular heads, rough at the 

 ends. There are two strong oblique ridges springing 

 from near the pseudo-stigmata, which look like rudi- 

 mentary lamellae. Interlamellar hairs long, fine, seti- 

 form. 



Legs short, the fourth pair not reaching the hind 

 margin ; rather thick, rough, gradually diminishing in 

 thickness, but each joint is slightly enlarged at the 



