148 [Assembly 



On one specimen the head and a few of the anterior segments had 

 been lost and renewed, but the branchiae were still wanting. 

 Common in sand at low water, 



ScoLEcoLEPis TENUIS Vevrill, 



Invert. Animals of Vineyard Sound, etc., p. 601. 1874. 



Reported by Verrill from Great Egg Harbor, in sand at low 

 water. We failed to find it. » 



SPIO (0. Fahr.) (Ersted. 

 (Ersted. Annulatorum Dauicorum Conspectus, p. 39. 1843. 



Spio setosa Verrill. 



Neritie coniocepliala ? A. Agassiz. Annals Lvceum Nat. Hist, of X. Y., vol. viii, 



p. 333, pi. X, figs. 39-45. 1866. (See Verrill, op. cit.) 

 Spio setosa Verrill. Invert. Animals of Vineyard Sound, etc., p. 602, pi. xiv, 



fig. 77 (copied from Agassiz). 



Verrill says of this species that the lateral lobes of the head are 

 shorter than the median ; this is true in alcoholic specimens ; the 

 reverse is the case in living forms. Common in sand at low water. 



POLYDORA 5osc. 



Histoire Naturelle des Vers, vol. i. 1802. 



PoLrDORA HAMATA Wehster. 



Annel. Chset. of the Virginian Coast, p. 251, pi. viii, figs. 111-116, pi. ix, figs. 

 117, 118. 1879. 



Common, living in galleries in shells. From low water to fifteen 

 feet. 



POLYDORA LIGNI U. SJ). 

 PLATE {xj, viii, FIGS. 45^7. 



Head deeply emarginate in front, lateral lobes bluntly rounded 

 (fig. 45), pointing forward and outward ; lateral margins, in front 

 and back of the eyes, concave ; opposite the eyes (middle third) 

 convex; a rounded carina runs back to the middle of the fourth 

 segment ; at the front margin of the third segment this carina bears 

 a small conical papilla, always distinct, even on the smallest speci- 

 mens. 



Eyes four, black, circular, placed at the angles of a trapezoid ; 

 anterior pair larger than posterior. 



Tentacles short, with the usual structure, colorless, without mark- 

 ings. 



Dorsal cirri, long and stout on the anterior segments, smaller on 

 those havinsr branchiae. 



