242 ^OLIDIDiE. 



length, subulate, their superior halves silvery, the dorsals delicately 

 ringed alternately larger and smaller, serrate at the edges. Foot 

 with the angles greatly protracted, tentaculiform, a muscular opaque 

 band passing along the anterior edge from one to the other, looks 

 like a portion wholly detached from the foot. Length, about one 

 inch ; breadth, three tenths of an inch. 



Found in September, accompanied by ova, in Charles River, at 

 the Bath-house, Craigie's Bridge. Rather common ; in various parts 

 of Boston Harbor by dredging, and at Lynn {Stimpson). 



In size and general characters this species approaches closely to 

 jE. coro7iata, Forbes, differing mostly in coloration. I have regarded 

 it as the jE. Bostoniensis, though it will be seen, by comparison with 

 the original description and figure, that there is a variance in many 

 minor particulars ; but as there is no incompatibility in essential 

 characters, and as no other animal has been found in any way an- 

 swering to Mr. Couthouy's description, it seems better to ascribe the 

 differences to more accurate delineation and better opportunities for 

 observation. Mr. Couthouy is doubtless in error in representing the 

 tentaculiform dilatations of the angles of the foot as belonging to a 

 separate piece, as this would lie contrary to all analogy. The ova 

 are expelled in a bobbin-like string, which is looped and festooned 

 and attached to stones or logs in a loose coil. It is a very active 

 and beautiful species. It feeds on zoophytes. 



.ffiolis rufibranchialis. 



Plate XIX. Tigs. 269, 272. 



Body slender, tapering, white ; oral and dorsal tentacles sub-equal ; branchiae 

 nearly linear, variable in length, disposed in six or seven clusters on each side, 

 interior of a bright vermilion, with an opaque-white rim near tip; anterior angles 

 of foot prolonged and folded transversely. 



Eolidia nifihranrhinlis, Johnst. in Loud. Mag. Nat. Hist. v. 428 ; Ann. Nat. Hist. i. 121. 



EoUdiu Emhietoni, Johnst. in Loud. Mag. Nat. Hist. viii. 79. 



Eolis rufibrnricliiidis, Alder and Hancock, Monog. Brit. Nudib., Fam. 3, pi. 14. 



Enlis Mananensis, Stimpson, Mar. Invert. Gr. Manan, 2G (1853). 



toll's Mananensix, Stimpson, Check Lists, 4 (1860). 



Body slender, tapering to a fine point, watery white with an 

 opaque-white line along the middle of the back. Dorsal tentacles 

 moderately long, tapering, wrinkled, the wrinkles varying in depth 

 constantly, yellowish-white, sometimes tinted brownish, pale at tips 

 and having an opaque-white line on the posterior face. Oral tenta- 



