60] 



Gen. 7. Erichthonius, M. Edw., 18:30. 



Syn. : Cerapodiiia, M.-Eilw. 



» Cerapus, Tenipleton (not !Say). 



» Pyctilus, Dana c?. 



» Dercothoi", Dana 9. 



Body slender, subdepressed, with very small coxal plates, the anterior 

 pairs of which are no larger tlian the posterior; epimeral plates of metasotne 

 small; urosorae narrow and elongated. Cephalon having the frontal part 

 considerably produced, with the lateral lobes tumid and more or less projec- 

 ting. Eyes well developed, and pjaced within the latei'al lobes of the cephalon. 

 Antennae slender, subequal, and edged posteriorly with fascicles of slender 

 bristles, the superior ones without any accessory appendage, the inferior 

 ones issuing at a considerable distance behind the superior, and having the 

 antepenultimate joint of the peduncle unusually elongated; flagella in both 

 pairs multiarticulate. Anterior lip produced in front to an acuminate projec- 

 tion ; posterior lip with well-defined inner lobes. Mandibles short and stout, 

 with the palp much elongated, and having the terminal joint lamellar and 

 densely setiferons. Maxillae normal. Maxillij^eds with the palps comparatively 

 narrow. Gnathopoda very unequal, the anterior ones rather small, and of 

 similar structure in the 2 sexes, with the carpus comparatively large and 

 lamellarly expanded below, propodos short but broad, nearly triangular in 

 form. Posterior gnathopoda in female considerably larger than the anterior, 

 carpus produced below to a setiferous lobe, propodo.s rather expanded, with 

 the palm well defined ; those in male of enormous size and complexely chelate, 

 the carpus being exceedingly large, and sending ofi" from its end inferiorly an 

 acuminate, thumb-like process, propodos narrower than the carpus, and having 

 the palm imperfectly defined, dactylus large and, when closed, crossing the 

 carpal process. Anterior pairs of pereiopoda with the basal joint lamellarly 

 expanded; the 3 posterior pairs successively increasing in length, and having 

 the basal joint oval in form; dactylus of antepenultimate pair inverted. 

 Branchial lamellae small, wanting at the base of the posterior gnathopoda; 

 incubatory lamellae large and broad. Last pair of uropoda with a single 

 lamellarly unguiform ramus. Telson short and broad with 2 densely spinous 

 prominences above. 



Eeniarls. — The present genus was established in the year 1830 by 

 Milne-Edwards, to include one of the species described below. For the form 

 recorded by Templeton as Cerapus abditus he established another genus, 



