198 



Occurrence. This form is found parasitic in the branchial cavity of spe- 

 cies of Leander (Palsemon), such as L. scrratus, squilla and Eathfcei, sometimes 

 on the left, sometimes on the right side, in every case causing a strong lateral tuber- 

 osity of the carapace, similar to that caused by Bopyroldes liippolytes (fig. 2 x). 

 It has not yet been recorded from Norway; but as at least 2 of the species of 

 Lei'ut-ilrr, which at times are infested by this parasite, are very common on 

 our coasts, it is most likely that, on a closer investigation, it will be found 

 to belong to the fauna of Norway. The figures of the female here given 

 are from a specimen found on Leander serratiis from the Danish coast; that of 

 the male is copied from Sp. Bate and Westwood's work. 



Distribution. Danish coast (Meinert), British Isles (Sp. Bate), coast of 

 France (Giard & Bonnier), Mediterranean. 



Gen. 2. BOpyrOideS, Stimpson, 1864. 



Syn : Bopyrus, Kroyer (not Latreille) 

 Gyge, Sp. Bate (not Corn. & Pane.) 



Generic Characters. Body of female resembling that of Bopyrus, though 

 having the cephalon less broad, the lateral parts of mesosome perfectly smooth, 

 and the metasome distinctly segmentated. Posterior antennae 4-articulate. 

 Terminal joint of maxillipecls well defined, but rather narrow. 1st pair of incu- 

 batory plates concealing the whole ventral face of cephalon, and having the 

 distal segment broadly securiform; the succeeding pairs, as in Bopyrus, widely 

 apart. Legs short, more or less concealed within the lateral margins of the 

 mesosome. Pleopoda obsolete, being replaced by slight fleshy ridges. Uropoda 

 wanting. Mtdc with the segments of metasome fused together. Parasitic in 

 the branchial cavity of species of the genus kpirontocaris (Hippolyte). 



BemctrJcs. This genus, established by Stimpson, is nearly allied to 

 Bopyrus, from which it is chiefly distinguished by the absence of true pleopoda, 

 and by the male having all the segments of metasome fused together. The 

 species of this genus are found parasitic in the branchial cavity of different 

 Carida belonging to the genus Spirontocaris Sp. Bate (Hippolyte Kroyer). To 

 the fauna of Norway belongs only a single species, to be described below. 



