DR WILLEY FROM THE SOUTH SEAS, 399 



Turning now to a systematic survey of the material, we may notice at the outset 

 the relative extent to which the various groups of Macrura and Stomatopoda are 

 represented. 



There are seven species of Stomatopoda, belonging to six out of the nine genera 

 of that order. Of these species one, a Squilla, is new. lu the Macrura. the Penaeidea 

 are represented by two species of Penaexis, the Stenopidea by one species of Stenopus, 

 the Caridea by 32 species from 17 genera, the Loricata by .5 species from 3 

 genera, the Thalassinidea by three species from as many genera, and the Anomala bv 

 32 species from 9 genera. The 19 new species in this suborder are distributed 

 as follows: in the Caridea there are 13, in the Thalassinidea 2, in the Loricata one, 

 and in the Anomala three. 



Of the 38 genera in the whole collection, the most numerously represented is 

 Alpheus, with six species ; PericUinenes, on the other hand, has both absolutely and 

 relatively' the largest number of new species (four out of five). 



Conspicuous by their absence are the Astacidea and the Crangoninea. 



Sub-class. THORACOSTRACA. 



Order. STOMATOPODA. 



Family. Squillidae. 



Genus. Protosquilla, Brooks, 1886. 

 1. Protosquilla cerebralis Brooks, 1886. 



Protosquilla cerebralis Brooks, 'Challenger' Stomatopoda, p. 72, PI. XIV. Figs. 2 

 and 3, XVI. Figs. 2 and 3 (1886); Borradaile, P. Z. S. 1898, PL V. Fig. 6a. 



Brooks's specimens of P. cerebralis were all females. Fortunately, however, Dr 

 Willey's collection contains a male specimen, so that it has been possible [P. Z. S. 

 loc. cit.l to figure for this species the peculiar structure on the endopodite of the fir.«t 

 abdominal appendage of male Stomatopoda. 



The outer leaf of the last joint of this organ is smaller than the inner, <.ii 

 which it is borne as a lobe, and from which it is not sundered by a suture. The 

 fixed limb of the pincers is hook-shaped, while the movable limb is bent sharply 

 and of a shape something like that of a boomerang. The first joint is produced on 

 the outside at the free end. 



Two % from Sandal Bay, Lifu, Loyalty Islands. One ^ from Pigeon Island, New 

 Britain. 



' With the exception, of course, of the new genera Palaemonopsis, Parhippolyte, and Alpheinus, each 

 founded for a single new species. 



54-2 



