162 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



Livoneca ovalis White, List Crust. Biit. Mus., p. 109, 1R47. — CiimothoaovaUs Stiy, 

 Jour. Acad. Nat. Sci. Phil., vol. i, p. 394, 1818. 



White and several other British carcinologists use the orthography 

 Zironeca; but in the Dictionnaire des Sciences naturelles. tome xii, 

 where the genus is estabUshed by Dr. Leach, the name occurs, in French 

 and Latin, nine times on pages 352 and 353, spelled alw.ays with v as the 

 third letter. I have, therefore, adhered to that orthography, although 

 there is reason for supposing that Dr. Leach intended to use the form 

 Lironeca. 



Parasitic on Bluefish, etc. ; not yet found north of Cape Cod. 



Anthura polita Stimpson, Proc. Acad. Nat. Sci. Phil., vol. vii, p. 393, 1855. — Antliura 

 hrioniea Harger, Eep. U. S. Fish Com., part i, p. 572 (278), 1874. 



A southern species, not found north of Cape Cod until the summer of 

 1878, when it was taken at Gloucester, Mass. Usually found among 

 Eel-grass or mud in shallow water. 



Parauthura hiSLCliiata.:^^ Anthura hrachiaia Stimpson, Mar. Invert. Grand Manan, p. 

 43, 18.33. 



A northern species, but found as far south as Vineyard Sound, from 

 27 to 115 fathoms. 



Ptilanthura tenuis Harger, Am. Jour. Sci., Ill, vol. xv, j). 377, 1878. 



Bare, but found throughout the New England coast. The remarkably 

 elongate fiagellum of the antennulje belongs to the males only. 



Gnathia cerina = Praniza ceriva Stimpson, Mar. Invert. Grand Manan, p. 42, pi. iii, 

 fig. 31, 1853; and, also, Anceus Americanus Stimpson, op. cit., p. 42, 1853; the 

 former being the female form and the latter that of the adTilt male. 



A northern species, not yet found south of Cape Cod, occurring in 

 from 10 to 220 fathoms, and, in the young stages, parasitic on fish. 



Tanais vittatus Lilljeborg, Bidrag til Kiinn. Crust. Tanaid., p. 29, 1865. — Crossurus 

 vittatus Eathke, Fauna Norwegens, (Nova Acta Acad., vol. xx,)p. 39, id. i, figs. 

 1-7, 1843. 



This species has been found at Noank Harbor, Conn., and will proba- 

 bly be found at other localities on our coast. I Tiave had no European 

 specimens for comparison, and, unfortunately, have not had access to 

 some important European literature on the subject, but do not know of 

 any character by which to distingiiish it from Rathke's s^jecies, and have 

 t,herefore regarded it as identical. 



This genus is well sej)arated from the next by the pleon, which bears 

 only three pau'S of pleopods and uniramous lu-opods, and by the remark- 

 able incubatory sacs attached to the fifth thoracic segment of the 

 females, and unlike anything else found among the Isopodu. They have 

 been described by Eathke, Willemoes-Suhm, and others. 



Leptochelia algicola= Pcwatewais algicola liavgev, Aui. Jour. Sci., Ill, vol. xv, p. .377, 



1878. — Leptochelia Edwanhil Bate and Westwood, Brit. Sess. Crust., vol. ii,p. 

 134, 18G8, (males).— Ta/iaw /?»))( nurger, Eep. U. S. Fish Com., part i, p. 573 

 (279), 1874, not of Stimpson. 



A male specimen, received from Guernsey, through the kindness of 



