294 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [588] 



This species is closely allied to P. pulchella Malmgren, from Northern. 

 Europe, but differs somewhat iii the form of the head, which is shorter 

 and rounder in the latter ; the branchiae also differ in form. It is a very 

 active species, and secretes a large quantity of mucus. 



ETEONE ROBUST A Yerrill, sp. noy. (p. 488.) 



Body large, stout, depressed, broadest in the middle, tapering gradu 

 ally to each end. Head small, about as long as wide, convex, with a me 

 dian depression 5 the sides rounded; front obtusely rounded. The four 

 frontal antennae are very small, short, obtuse, less than half the diameter 

 of the head. Eyes very small, black. Tentacles very small and short? 

 tapering, their length about one-half the diameter of the head, the two 

 pairs about equal. BranehiaB small, sessile, anteriorly very small, oval, 

 obtuse; in the middle region rounded, sub-oval. Color dark green, with 

 the anterior portion somewhat paler, and with light green transverse 

 bands between the segments; lateral appendages pale green. 



Length, 125 mm ; breadth in middle, 5 mm ; length of head, 0.6 mm . 



Watch Hill, Rhode Island, under stones, between tides, April 12, 1873. 



ETEONE LIMICOLA Yen-ill, sp. nov. (p. 349.) 



Body very long and slender, tapering gradually to both ends; depressed, 

 and with deeply incised, elongated segments posteriorly; less depressed 

 and with shorter and less distinct segments anteriorly. Head small, 

 about as broad as long, the posterior angles well rounded, the sides with 

 a slight constriction in advance of the eyes, narrowing rapidly; front 

 narrow, convex ; antennae slender, about half the length of the head. 

 Eyes minute, inconspicuous. Tentacular cirri about equal to the length 

 of the head. Lateral appendages small on the anterior segments, becom 

 ing much more prominent farther back; anterior branchiae very small, 

 ovate, sessile; those farther back much larger, and narrow ovate. 

 Color, when living, light green throughout. 



Length about S0 mm ; breadth, including appendages, 1.5 mm . 



Great Egg Harbor, Xew Jersey, in mud at low- water. 



ETEONE SETOSA Yen-ill, sp. nov. 



Body long and slender, resembling the preceding in form, but some 

 what less slender. Head shorter and broader, the posterior angles 

 prominently rounded ; two slight notches or emarginations on the 

 posterior margin, the middle portion extending farther back than the 

 lateral; sides rapidly tapering; front narrow. Antennae less than half 

 the length of the head. Eyes small, but quite distinct. Tentacular 

 cirri scarcely as long as the head. Lateral appendages a little promi 

 nent on the anterior segments, but much less so than farther back; setae 

 numerous. The branchiae are small, sessile, and inconspicuous anteriorly ; 

 larger and ovate farther back. 



Length up to 75 mm ; breadth about 2 mm . 



Yineyard Sound, 6 to 12 fathoms, among ascidians. 



