A DESCRIPTION BY SAVIGXY 251 



Family 9. Pasipkceidce. 



The rostrum is small or obsolete, the mandibular ' palp ' 

 two- or one-jointed or wanting. The trunk-legs carry 

 exopods. The third, fourth, and fifth pairs are inferior 

 in size to the two pairs of chelipeds, the fourth being 

 generally smallest of all. 



Three genera are included in this family by Spence 

 Bate, and a fourth has been established by S. I. Smith. 

 One of these four is represented in British waters. 



Pasiplicea, Savigny, 1816, was established in a rather 

 casual manner in the footnotes to Savigny's celebrated 

 ' Memoires sur les animaux sans vertebres,' to receive the 

 Mediterranean species, Alplieus sivado, Eisso, which also 

 occurs in tolerably deep water off the coasts of England, 

 Ireland, and Scotland. Bell says that Savigny gave no 

 description of the genus, but he does in fact refer to the 

 peculiarity that the appendages of the trunk exhibit exo- 

 pods, as in species of Squilla and My sis. Moreover, when 

 insisting on the pediform character sometimes shown by 

 the maxillipeds, he subjoins a note that 'the Alpheu* 

 Sir ado of M. Bisso has really twelve thoracic feet em- 

 ployed in locomotion.' Lastly, in a note to the description 

 of the maxillipeds of an Amphipod, he observes that ' in 

 Alpliem Sivado, the second joints of the two front cheli- 

 peds are united into the form of a lip, a peculiarity all the 

 more remarkable for its occurring in only one of the sexes.' 

 Subsequent writers do not appear to have repeated or ex- 

 plained this last observation. The figures of this species 

 in Risso, in Bell, and in the completed edition of Leach's 

 ' Malacostraca ' (1875), are misleading as to the real 

 shape of the animal, which is strongly bent at the middle. 

 The mouth organs examined in a British specimen differ 

 considerably from those depicted by de Haan for this 

 species, but approach very closely those figured by Spence 

 Bate for his Pa^siphcea cristata from the Fiji Islands. In 

 this genus the mandibular palp is wanting. The second 

 maxillipeds are quite devoid of exopod, which Spence Bate 

 notes as very unusual in the Macrura. Kroyer's Pasiplicea 



