202 A HISTORY OF RECENT CRUSTACEA 



N&phrops, Leach, 1819, lias the eyes wider than their 

 foot-stalks and reniform or kidney-shaped in accordance 

 with the meaning of the generic name. The scale of the 

 second antennae is large, reaching the end of the peduncle. 

 The first pair of trunk-legs are long, slender, and pris- 

 matic in shape, not very unequal. The type-species, 

 Nephrops norwegicus (Linn.), is distributed generally 

 through the seas of Europe, belonging not only to Nor- 

 way, but also to Great Britain and the Mediterranean. It 

 is a beautiful species both in form and colouring. Accord- 

 ing to Spence Bate, the branchial arrangement is identical 

 with that of the common lobster, but Huxley draws a 

 slight distinction, saying that ' the branchial plume of the 

 podobranchia3 of the second maxillipeds is small or absent, 

 so that the total number of functional branchiae is reduced 

 to nineteen on each side' in Nephrops, as compared with 

 twenty in the lobster. 



Sars has figured and described the ' second larval stage ' 

 (see Plate IX.), 1 the ' last larval stage,' and the ' first post- 

 larval stage ' of this species. The larval pleon is highly 

 remarkable, not so much on account of the great dorsa 

 spines that arise from the fourth, fifth, and sixth segments, 

 as of the telson, which spreads itself out into two ciliated 

 and spinulose spine-like branches, which together make its 

 arch equal in breadth to the length of the animal. 



A second species, Nephrops Thomsoni, Spence Bate, 

 has been taken between Australia and New Zealand, and 

 in the Philippines. 



Eunephrops, S. I. Smith, 1885, is very near to 

 Neplirops, except that, like the American lobster, it has a 

 well-developed podobranchia to the second maxillipeds, 

 and the scale of the second antennae is very small. The 

 type species, Eunephrops Bairdii, was taken in the 

 Caribbean Sea. 



Astdcus, Leach, 1814, has the eyes not wider than the 

 foot-stalks and subglobose. The scale of the second an- 

 tennae is spine-like, not reaching the end of the peduncle. 



1 The form norvegicus, accidentally used on the Plate, is not the 

 original spelling, but a later refinement. 



