136 CRUSTACEA. 



This species might be embraced under the description of Leudppa 

 Ensenadce of Milne Edwards and Lucas (D'Orbigny's S. America, 

 Crust., p. 9, pi. 5, fig. 3) ; but the figure represents a species with 

 different characters. The Ensenadce in this figure, has proportionally 

 a shorter beak, with the two horns in contact and obtuse ; the carapax 

 is less perfectly triangular, and the several regions are much more 

 pronounced. The lateral margin in the Icevis is thin, slightly bending 

 upward, and the teeth are notches in the thin margin, or subacute 

 undulations in its outline, and not tubercles, " dont les trois post&- 

 rieurs sont arrondis." The legs have a narrow crest or a trenchant 

 edge. The outer edges of the basal joints of the outer antennae are 

 parallel or very nearly so, and not divergent backward as in the 

 figure of the Ensenadce; and the beak is open at the furcation. The 

 posterior lateral tooth of the carapax has the margin behind curving 

 around, so as to terminate against the surface of the carapax. 



II. PARTHENOPINEA. 



THE PARTHENOPINEA, as stated on a preceding page, are intermediate 

 between the Maia and Cancer groups, having the characters there men- 

 tioned. The anterior legs are usually the longest. The form may be 

 transverse, or slightly oblong. The genus Trichia agrees nearly with 

 Parthenope in the character of the orbit, the position of the base of 

 the outer antenna?, and in many other characters; and although its 

 anterior legs are but little longer than the following pairs, it evidently 

 pertains to this group, being in some points intermediate between it 

 and Dromia. 



LAMBRUS RHOMBICUS. 



Carapax non oblongus, rhombiciis (fere quadratus) , ad medium latior, 

 posticd et lateraliter rotkndatus, antice triangulatus, poiie oculos non 

 constrictus, superfieie superiore incequali, tuberculis parvulis parce 

 ornatd, in regione laterali super basin pedum 2dorum tuberculo 



