INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 603 



Spio eobusta Yerrill, sp. no v. (p. 345.) 



Body stout, broadest anteriorly, tapering posteriorly, but little de- 

 pressed except anteriorly, very convex beneath, flattened above. Head 

 broad) somewhat angular; the median lobe truncated and slightly eniar- 

 ginate in front ; lateral lobes a little shorter, wide, obtuse in front, 

 slightly angulated laterally ■; a small median, conical elevation on the 

 posterior part of the head. Antennae long, rather stout. Branchiae 

 long, narrow, tapering. Upper ramus of the feet with a small, obtuse 

 setigerous lobe, bearing a small fascicle of short setae, considerably 

 shorter than the branchiae, even on the anterior segments, and a foli- 

 aceous process arising behind the setigerous lobe, broadly rounded on 

 its thin outer edge ; the upper end free and obtusely pointed ; farther 

 back the setae are shorter and the foliaceous process smaller and less 

 prominent. The lower ramus on the anterior segments has a small, 

 prominent, semicircular foliaceous process and a small, dense fascicle of 

 short setae, crowded in several transverse rows ; on the eighth and sub- 

 sequent segments the foliaceous processes become larger and wider, and 

 the setae more numerous, crowded, and partly uncinate ; still farther 

 back the setae are nearly all uncinate, except a very small ventral tuft 

 of slender ones, and form long, double, transverse rows, projecting but 

 little beyond the surface. Color greenish. 



Length, 50 mm , or more; breadth, 3 mm to 3.5 mm . 



Wood's Hole and Naushon Island; in sand, at low- water mark. 



Polydora ciliatum Claparede(?). Plate XIY, fig. 78. (p. 345.) 



A. Agassiz, On the Young Stages of a Few Annelids, in Annals Lyceum Nat. Hist. 

 of New York, vol. viii, pp. 323-330, figs. 26-38, 1866 (embryology). 



Naushon Island and Massachusetts Bay ; in muddy sand, at about half- 

 tide (A. Agassiz). 



The adults of this species were not found by us. The young were 

 frequently taken in the towing-nets. 



A young Polydora, belonging perhaps to a different species, was 

 dredged off New Haven, in 4 to 6 fathoms, shelly bottom. It was about 

 12 mm long. The color was pale yellow, with small black spots along 

 the sides between the fascicles of setae ; a red dorsal vessel ; antennae 

 white. 



Ophelia simplex Leidy. (p. 319.) 



Marine Invert. Fauna of Rhode Island and New Jersey, p. 16, 1855. 

 Body short, smooth, iridescent, well rounded above, flat below ; 

 usually found coiled up, so that the extremities meet, or nearly so, and 

 resembling in general form the larvae of certain beetles and flies. Head 

 very acute conical ; the buccal segment suddenly enlarges ; mouth be- 

 neath, with thick evertile lips, the lower one generally protruded as a 

 large rounded lobe. Posterior end terminated by about ten unequal, 

 round, blunt, fleshy, simple papillae, of which the two ventral ones 



