160 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



Idotea irrorata Edwards, Hist. nat. des Crust., tome iii, p. 132, 1840. Stenosoma irro- 

 rata Say, Jour. Acad. Nat. Sci. Phil., vol. i, p. 423, 1818. Idotea tricuspidata 

 Desmarest, Diet, des Sci. nat., tome xxviii, p. 373, 1623; Cousid. Crust., p. 289, 

 1825. 



This species is common throughout the coast of New England, but is 

 more abundant southward, being to a great extent replaced toward the 

 north by the next species. 



A comparison of English and European specimens with our own 

 leaves no doubt of the identity of the species on the opposite coasts of 

 the Atlantic. Being a common European species, it has been mentioned 

 by many authors under a variety of names, which are more fully quoted 

 and discussed in the report. Say's name appears to be the earliest that 

 can be certainty connected with the species. 



Idotea phosphorea Harger, Eep. U. S. Fish Com., part i, p. 569 (275), 1874. 

 Found throughout the coast, but more abundant northward. 



Idotea robusta Kroyer, Naturhist. Ticlssk., II. Bind ii, p. 108, 164G; Gaimard's Voyage 

 en Scaiidinax ic. etc., Atlas, pi. xxvi, iig. 3 a-r, ISI'J. 



A pelagic species. 







Synidotea nodulosa 1 larger, Am. Jour. Sci., Ill, vol. xv, p. :'.74. 1-78. Idotlica nodidosa 

 Kroyer, Naiurliist. Tidssk., II. Hind ii, p. KM), IS.Hi; Gaimard's Voyage en 

 Scandinavic, etc.. Atlas, pi. xxvi, fig. 2, 1H'.. 



A northern species, found at llalit'ax, N. S., and 1LV> miles southward, 

 in from 16 to 190 fathoms. Also from George's Bank. 



Synidotea bicuspida = Idti<i liii-ii^iiiln Owen. Voy:me nl' the P.lossoiu, Crustacea, p. 

 '.L'. ]>1. xxvii, Iig. tl. \-:','J. Idntii'K uninimnitu Packard, Mem. Soe. Nat. Hist. 

 Boston, vol. i, p. 'JlHi, pi. viii, iig. ('>. l^liT '. Idotea pitlchra Lockington, Proc. 

 Cal. Acad. Sci., vol. vii. ]>. !.">, 1~77. 



The determination of the synonymy of this species rests principally 

 upon the work of .Messrs. Streets and Kingsley in the Bulletin of the 

 Essex Institute, vol. ix, p. 108, 1877. It has not yet been found south 

 of the Grand Bank. 



Erichsonia filiformis Harger, Rep. U. S. Fish (' part i, p. 570 (27(5), pi. vi, fig. 6, 



H74. Stenosoma filiformis Say, Jour. Acad. Nat. Sci. Phil., vol. i, p. 424, 1818. 



A southern species, not yet found north of Cape Cod. 



Erichsonia attenuata Harger, Rep. U. S. Fish Com., part i, p. 570 (276), pi. vi, iig. 27, 

 1874. 



Great Egg Harbor, Xew Jersey, and Xoauk, Conn. The species will 

 probably be found at other localities, among eel -grass, on the southern 

 shore of New England. 



Epelys trilobus Smith, Rep. U. S. Fish Com., part i, p. 571 (277), pi. vi, fig. 28, 1874.- 

 Idotea ti-iloba Say, Jour. Acad. Nat. Sci. Phil., vol. i, p. 425, 1818. 



A southern species, rare -north of Cape Cod, but extending, with some 

 other southern species, to Quahog Bay, on the coast of Maine. 



