202 A HISTORY OF RECENT CRUSTACEA 
Nephrops, Leach, 1819, has 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 antennz 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 norweygicus (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 
podobranchiz of the second maxillipeds is small or absent, 
so that the total number of functional branchiz is reduced 
to nineteen on each side’ in Nephrops, as compared with 
twenty in the lobster. 
Sars has figured and descr ibed the ‘second larval stage’ 
(see Plate IX ‘ 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 dorsal 
spines that arise from the fourth, fifth, and sixth segments, 
as cf 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, 8S. I. Smith, 1885, is very near to 
Nephrops, except that, like the American lobster, it has a 
well-developed podobranchia to the second maxillipeds, 
and the scale of the second antenne is very small. The 
type species, Hunephrops 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 
tenne is spine-like, not reaching the end of the peduncle. 
1 The form xorregicus, accidentally used on the Plate, is not the 
original spelling, but a later refinement. 
