REPORT ON THE CRUSTACEA MACRURA. 



833 



dorsal crest, but the specimens as a whole are so closely allied that it is difficult to 

 consider them as being more than varieties of the same species, and they both appear 

 to differ from the description given of Notostomus gibbos%is by A. Milne-Edwards 

 <inly in the unimportant feature of the small denticles on the rostrum, more especially 

 on the under side. It appears to me probable that the three forms belong to the same 

 species, but, in the present condition of zoology, it is very desirable that forms found 

 in very distant localities, though resembling each other in general aspect, should have 

 their details and points of distinction clearly determined. This form was taken off the 

 eastern coast of South America, near Pernambuco, in 675 fathoms ; Notostomus gibbosus 

 was taken off Grenada, in the West Indies, at 626 fathoms, and Notostomus perlatus was 

 procured off the Island of Celebes, at 2150 fathoms, a depth of about two miles and a half. 



Notostomus longirostris, n. sp. (PI. CXXXV. fig. 4). 



Carapace more arched posteriorly, and less over the frontal region than in Noto- 

 stomus imtentissimus or Notostomus perlatus; laterally marked with four long 

 carinas and one semi-carina. Rostrum as long as the carapace. The dorsal carina is 

 furnished with minute denticles from the posterior margin of the carapace to the 

 extremity of the rostrum, gradually increasing in size as they advance anteriorly ; the 

 under surface is armed with fourteen teeth, which are rather larger than those on the 

 upper surface. 



Telson equal in length to the outer plates of the rhipidura, dorsally grooved, 

 laterally depressed, the longitudinal ridges between the depressions and the dorsal 

 groove being furnished with three or four distant minute spinules. 



Habitat.— Station 195, October 3, 1874; lat. 4° 21' S., long. 129° 7' E; off Ban da 

 Island; depth, 1425 fathoms; bottom, blue mud; bottom temperature, 38°. One 

 specimen, male. Trawled. 



This species corresponds in many respects with A. Milne-Edwards' description of 

 Notostomus elegans, and is an intermediate form between it and Notostomus murrayi. 

 It has the rostrum half as long again as the scaphocerite, and has fourteen teeth on the 

 lower surface. It has the dorsal carina more arched towards the posterior or cardiac 

 region, and less so anteriorly, and has four lateral carinas instead of two. 



(ZOOL. CHALL. EXP. — PAET LH.— 1887.) Fff 105 



