Serolis, Leach. 



But a single species is known, the Cymothoa paradoxa. Fab. 

 The antennae are placerl on two lines, and terminated by a pluri- 

 artieulated stem. Under the three first segments of the tail, 

 between the usual appendages, there arc three others, trans- 

 versal and terminated posteriorly in a point *. 



Sometimes the eyes arc lateral and not placed en tubercles ; the 

 tail is composed of five or six segments. 



Here the organ of sight is not formed of smooth, granular, ap- 

 proximated eyes ; the antennae are placed on two lines, and consist of 

 seven joints at least ; the six anterior feet are usually terminated by 

 a small, stout nail. 



In some, where the tail always consists of six segments, the length 

 of the inferior antenme never surpassed the half of that of the body. 



We Avill begin with those whose mandibles, as usual, are but 

 slightly, or in no degree salient. 



Cymothoa, Fab. 



The antenna? nearly equal in length ; eyes scarcely apparent ; last 

 segment of the tail forming a transverse square ; the two pieces ter- 

 minating the lateral fins, linear, equal and styliform f . 



IcTiiYOPHiLus, Lat. — Nkrocila, Livoxeca, Leach. 



The antennae, equal in length, and but slightly visible eyes ; the 

 last segment of the body almost triangular ; the two pieces termi- 

 nating the lateral fins in the form of leaflets and laminae, the exterior 

 of which is largest in the Nerocilse, and of the size of the otlier in 

 Livoneca |. 



In the four following subgenera the superior antennae arc mani- 

 festly shorter than tlie inferior. 



In several, as in Cymothoa, all the feet are terminated by a small, 

 stout, and strongly curved nail ; the last eight are not spinous ; the 

 eyes a,re always separated and convex. They form three genera in 

 the system of Leach, but may be united in a single subgenus, under 

 the common denomination of one of them, or the 



Canolira, Leach. — Anilocra, Olencira, Ejusd. 



The laminee of tho fins in the Olencirae § are narrow and armed 

 with spines. In the Anilocrae || the external leaflet of the same 

 j>arts is longer than the internal ; the reverse is the case with the 

 Canoline^. The eyes, besides, are but slightly granulous while in 

 the preceding that disposition is evident. 



* For other details consult Dcsmar., Consitl., p. 292 — 294. 



f Cymothoa ccslrum, Fab. ; Desinar, Consid., XLVI, 6, 7 ; — C. imbricata, Fab. 

 For the other species, see Dcsmar., loc. cit. 



X See Desftiar., op. cit. p. 307, genera Nerucila and Livoneca, and varijus species 

 of Cymothoa; of Kisso, p. 310, 31 1. 



§ Desmar., Consid., p. 306. 



11 Desmar., Consid., Anilucre du Cap, XLVIII, 1. 



«|] Desmar., Consid., p. 305. 



