77 



Gen. :>. PetalOSarSia, Stubbing, 1H93. 



Syn : Pctalopus, G. 0. Sars. 

 PetitlniiH'ra, G. O. Sars. 



ic CliHracti'rH. General form of body about as in I'xcntloc/tnna, though 

 comparatively shorter and more compact, at least in female. Integuments greatly 

 indurated. Carapace large, with the upper face flattened and declining obliquely 

 to the prominent pseudorostral projection. Exposed segments of trunk smooth. 

 Ej-e less perfectly developed than in Pseudocuma. Superior antennae with the 2nd 

 j'oint of the peduncle lamelliformly dilated, last ioint very small. Inferior antennae 

 in female distinctly biarticulate, with an apical and a lateral seta, those in male 

 attaining the length of the body. Oral parts about as in Pseudocuma. First pair 

 of legs of a rather peculiar appearance, the ischical and meral joints being firmly 

 connected with each other, and the carpal joint enormously developed, folia- 

 ceous, last 2 joints small and admitting of being bent in against the inner face 

 of the carpal one. Second pair of legs comparatively short; 3rd and 4th pair 

 in female with a very small rudimentary exopodite. Pleopoda of male resembling 

 in structure those in Pseudocuma. Uropocla with the stem much shorter than the 

 rami, the inner of which is densely hairy inside. Telson semicircular, unarmed. 

 Remarks. This genus was established by the present author in the year 

 1864; but as the name at that time proposed, Petalopus, and also that substituted 

 later, fetalomera, had been previously appropriated in Zoology, the Rev. Mr. 

 Stebbing has recently proposed to name the genus as above, a compound indeed, 

 which is quite sure not to have been previously employed. The genus is closely 

 allied to Pseudocuma, more so, indeed, than at first supposed. The peculiar 

 structure of the 1st pair of legs still seems, however, to warrant the validity of 

 the genus. We know at present of only a single species, to be described below. 



3. Petalosarsia declivis, G. 0. Sars. 



(PI. LIV). 

 Petalopus declivis, G. O. Sars. Om den aberrante Krebsdyrgruppe Cumacea, p. 72. 



Syn : Pctalomera declivis, G. 0. Sars. 



Specific Characters. Female. Body comparatively short and compact, 

 with the anterior division rather tumid and sharply marked off from the posterior, 

 dorsal face boldly vaulted behind the middle. Carapace nearly twice as long as 



11 Crustacea. 



