9 8 



Bali Sea, where a well-preserved, almost adult, male specimen was captured by the "Siboga". 

 Two new species were discovered by this expedition, firstly Nephr. Sibogac, a form closely 

 allied to Nephr. Thomsoni and Nephr. Challengcri and nine well-preserved and adult specimens 

 of which were taken off the Kei-islands, and finally Nephr. arafurensis from the same Station. 



The indopacific species and Nephr. rubellus from the coast of Brazil have some characters 

 in common, which are wanting in Nephr. norwegicus, the european representative of this genus. 

 Posterior to the cervical groove the carapace is provided in the former with 7, in Nephr. norwegicus 

 only with 5 longitudinal ridges; in the former the margins of the rostrum are continued back- 

 wards to near the cervical groove, as a pair of strong outstanding carinae, formed by three or 

 more trenchant spines which decrease in size from before backwards, but these outstanding carinae 

 are wanting in the Norway Lobster; in the latter the antennal spine is very small, in the other 

 species, however, one observes a great trenchant, wing-like spine, the scaphocerite, finally, 

 narrow and lanceolate in the Norway Lobster, appears broader and often almost circular in 

 the other species. 



Nephr. norwegicus occurs, according to C. M. Selbie (The Decapoda Reptantia of the 

 coasts of Ireland, London, 19 14, p. 48) "in greatest numbers in depths of 10 — 40 fathoms in 

 the Irish Sea, on the west coast it also extends into deep water down to more than 300 fathoms". 

 The greatest depth is recorded by Senna, a specimen having been taken west of Sicily, at 

 416 — 450 fathoms. Nephr. rubellus occurs at depths between 33 and 55 fathoms. The indo- 

 pacific species are also found in rather deep water, so e. g. Nephr. Thomsoni at 100 fathoms, 

 Nephr. andamanicus at depths varying between 185 and 405 and Nephr. Sibogae at 172 fathoms. 



Key to the indopacific species of the genus Nephrops Leach. 



a l Carapace smooth or finely granulate and pubescent. 



6 1 Terga of 2 ,ld — 5 th abdominal somites appearing conspicuously sculp- 



tured to the naked eye. First pair of legs with the longitudinal 



ridges on the chelae very prominent and spinulose. 



c, Largest spines at base of rostrum directed inward, with their 



upper border distinctly curved downward ; posterior to these 



spines 4 or 5 pairs of smaller spines. Two pairs of spines 



on 6 th somite of abdomen japonieus Tapp. Can. 



(C. TAPPARONE CANEFRI, Intorno ad una nuova specie di Nephrops, genere di 

 Crostacei decapodi Macruri, Torino, 1873, in: Mem. R. Accad. Sc. Torino, 

 Ser. II, T. XXVIII). 



c„ Largest spines at base of rostrum directed obliquely upward and 

 slightly outward, with the upper margin straight; posterior to 

 these spines only 2 pairs of smaller ones. No two pairs of 



spines on 6 th somite of abdomen andamanicus W.-Mas. 



b„ Terga of 2 nd — 5* abdominal somites appearing to the naked eye 

 almost smooth. First pair of legs with the longitudinal ridges 

 on the chelae not very prominent, more or less granulate. 



