Annelida Ch^etopoda of New Jersey. 119 



SPIO (0. Fabr.) (Ersted. 

 CErsted. Annuiatorum Danicorum Conspectus, p. 39. 1843. 



Spio setosa Verrill. 

 Nerine coniocephala ? A. Agassiz. Annals Lyceum Nat. Hist, of N. Y., vol. viii, 



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

 jSpio setosa Verrill. Invert. Animals of Vineyard Sound, etc., p. 602, pi xiv, tig - . 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 Bosc. 



Histoire Naturelle des Vers, vol. i. 1802. 



Polydora hamata Webster. 



Annel. Chset. of the Virginian Coast, p. 251, pi. viii, figs. 111-116, pi. ix, figs. 117, 

 US. 1879. 



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

 Polydora ligni n. sp. 



PLATE V, FIGS. 45-47. 



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 

 specimens. 



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

 larger than posterior. 



Tentacles short, with the usual structure, colorless, without markings. 



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

 branchiae. 



Branchiae begin on seventh segment, long, finger-shaped, colorless, with red 

 centre ; they are found on all segments after the sixth, except a small but vari- 

 able number of posterior segments. 



Setae of the fifth segment (fig. 46) eight to twelve in number, stout, apex 

 bluntly rounded and slightly curved ; a little below the apex is a small tooth on 

 the side of the seta, forming a very small angle with the seta ; dorsal setae long, 

 capillary, longer behind than in front ; ventral setae (fig. 47) short, bidentate ; 

 inner tooth very long, sharp, given off at right angles to the body of the seta ; 

 outer half covered by a membrane. 



Terminal sucker broad, shallow, white ; anal opening surrounded by low 

 papillae. 



Body colorless, except as colored red or brownish-red by the blood and con- 

 tents of the intestine ; on either side of the carina a brown line, diverging in 

 front, and passing to the outer base of the tentacles. 



Length, l-4"" u ; segments numerous. 



Found on water-soaked wood, living in crevices, etc. 



Tubes made of dirt, fragile, constructed with great rapidity. 



