I'LAi'VSCKLlD.K. 327 



1. Tliyropus ovoides. (Plate LII. fi}^. 7.) 



Typliis ovuidos, liisso, Cnisf. dv Nice, p. 122. pi. 2. 1'. 9. 

 Eilicanh, Hist, dvs Crust, iii. p. 5)7. 



Fii-st segment of the pereion short. The last two and the first tlireo 

 of the pleou rounded in the centre, gi\'ing a corrugated appearance 

 to the dorsal surface. Superior antimna) having a peduncle of 

 three joints, the middle joint being the shortest, the other two 

 directed at right angles from one another, fonuing an inverted 

 curve ; inferior margin thicldy covered with hairs, and sub- 

 apicuUy excavated on the upper margin to articulate with the 

 tlagelluin ; Hagellum minute, consisting of three articuli. Inferior 

 antenna; five-jointed ; second joint double the length of the first ; 

 third longer than the second ; fourth about one-third the length 

 of the third ; fifth scarcely half the length of the foiu'th. Gna- 

 thopoda subecpial : first pair haA"ing the carpus infero-anteriorly 

 produced to half the length of the propodos, with the inferior and 

 anterior margins strongly serrated ; propodos not so long as the 

 caroms, naiTow-oUiptical in form, Avith the inferior margin strongly 

 serrated ; dactylos short : second pair differing from the fii'st only 

 in being a little longer and not quite so robust. First two pairs 

 • of pereiopoda slender, cylindrical, having the mera, carpi and 

 propoda gcadually decreasing in length ; dactyla short, sharp, and 

 capable of being inflected against the projioda, where a small 

 denticle increases its prehensile capability. Third pair of pereio- 

 poda having the basos longer than the body is deep, subelliptic, 

 tenninating in an obtuse point, near which the ischium articu- 

 lates internally and posteriorly, which, together with the remain- 

 ing joints, is scarcely more than half the length of the basos, 

 against the inner side of which it is reversely inflected. Fourth 

 pair of pereiopoda having the basos as large again as that of the 

 third, terminating in a rounded apex ; the ischium articidates 

 about halfway on the intcrnfl surface between the centre and the 

 posterior margin, and rather more than half the length of the basos 

 from the bodj- ; remaining joints very short, together cciualling 

 about oue-foui'th the length of the basos ; carpus and propodos 

 with the margins on the flexible side serrated. Fifth pair of 

 percioi)oda sliort, about half the depth of the body, scarcely di- 

 lated, narrow, tipped with a small biarticulate tu])ercle that re- 

 presents the undi^velopcd portion of the limb. Tliree posterior 

 pairs of pleupoda biramous ; rami membranous. 



Length -^^tha of an inch. 



Hah. Taken 150 leagues south-west of tlie Azores by Capt. Du- 

 munier. Nice (Jiisso). 



