1862.] dr. baird on new phyllopodous crustaceans. 147 



5. Description of several New Species of Phyllopodous 

 Crustaceans, belonging to the Genera Estheria and 

 LiMNETis. By W. Baird, M.D., F.L.S. 



(Plate XV.) 



1. Estheria jonesi, Baird. (PI. XV. figs. 1, la, 15, Ic, Id.) 



Carapace of a comparatively hard, horny structure, and of a dark- 

 brown colour. Valves ventricose, rounded, ovate. Umboues pro- 

 minent, nearly central, but a little nearer anterior extremity ; invo- 

 lute and representing exactly those of a bivalve shell. Dorsal margin 

 short ; ventral rounded. Anterior extremity svpollen, rounded, 

 shorter than posterior extremity, which is somewhat compressed and 

 rounded. Ribs numerous and narrow. Those of the upper half of 

 carapace, from the umbo downwards, strongly developed, the edges 

 being raised and strongly beaded ; the interstices hollow, and more 

 sparsely dotted with rather small irregular-sized punctations. Ribs 

 of lower half of carapace, as far as the ventral margin, much smaller 

 than those of upper half, narrower, and much more numerous ; they 

 are punctate also ; but the interstices are so very narrow that no 

 sculpture can be seen. Internally the surface is quite smooth, and 

 of a dark-purple colour. 



Length of carapace, 6 lines ; breadth at umbo, nearly 5 lines. 



Hab. Brackish water. Island of Cuba (Dr. Bunker). Commu- 

 nicated by T. R. Jones, Esq. (Mus. Brit.) 



2. Estheria dunkeri, Baird. (PL XV. figs. 6, &a, Q h.) 



Carapace-valves broadly ovate and somewhat elongate. Umbones 

 prominent, and placed at some distance (rather more than a third) 

 from anterior extremity. Dorsal margin short, rather sloping. 

 Ventral margin nearly straight, or only slightly rounded. Anterior 

 extremity swollen, very convex, and rounded. Posterior extremity 

 elongate, more compressed, and not so rounded. The carapace is of 

 a uniform yellow horn-colour, thin, and translucent. Ribs numerous, 

 elevated, rather narrow, about twenty-seven in number, with the in- 

 terstices marked with shallow pits and extremely fine punctations. 



This species approaches somewhat to E. hrasiliensis, but differs 

 in the position of the umbones, those of E. dunkeri being further 

 from the anterior extremity. The relative size of anterior and poste- 

 rior extremities differs also, the former in E. hrasiliensis being much 

 broader than in the present species. It is a larger species also than 

 E. hrasiliensis. 



Length of carapace, 7 hues ; breadth at umbo, 4 lines. 



Hah. Zimapan, Mexico ; in fresh water (Br. Bunker), Com- 

 municated by T. R. Jones, Esq. (Mus. Brit.) 



3. Estheria lofti, Baird. (PI. XV. figs. 2, 2 a, 2 b.) 

 Carapace of a very light amber-colour, oval, rather swollen. Um= 



bones very prominent, elongate, placed near the anterior extremity. 

 Dorsal margin slightly sloping. Ventral margin rounded. Anterior 



