302 PROCEEDINGS OF THE ACADEMY OF [April, 



The single specimen is labelled Beaver Shoal, San Diego Bay, mud, 

 7/19/'05. 

 Glycera branchiopoda sp. nov. Pis. XX, XXI, figs. 155-159. 



A small, rather slender species, characterized by the well-developed 

 ligulate dorsal and ventral gills. The t3rpe is 90 mm. long without 

 proboscis; the maximum width, exclusive of parapodia, 2.8 mm., with 

 parapodia 3.5 mm. Proboscis, not fully extended, 22 mm. long, 

 2 mm. in diameter at base and 3.5 mm. at the distal end. 



Prostomium of the usual form, consisting of a broad, rugous, basal 

 region constituting about two-fifths of its length and a slender, some- 

 what depressed conical portion divided into seven annuli decreasing 

 in size regularly from base to apex, the basal three aggregating con- 

 siderably more than one-half of its length. Terminal segment very 

 small, dome-shaped, bearing the four minute apical tentacles which 

 are divergent and all directed somewhat ventrad, the dorsal slightly 

 longer than the ventral. There is a median dorsal and a median 

 ventral groove, the latter being the better developed. 



Peristomium closely united with prostomium, divided below by the 

 large mouth. Metastomial region increases in diameter to about XL, 

 from which the body tapers to the caudal end. Anterior segments 

 very short and crowded, the first with modified parapodia closely 

 crowded against the head. Remainder of the body nearly terete, 

 the segments strongly arched above and slightly flattened below. 

 Anteriorly they are at least eight times as wide as long, but increase 

 gradually in length while decreasing in width until the ratio is two to 

 one. All segments are strongly and completely triannulate and the 

 annuli are of nearly equal width, only the third or postpodal being 

 slightly larger than the others, especially posteriorly where they are 

 marked above by a straight cross-furrow. On the short and crowded 

 anterior segments the prepodal annulus is frequently united with the 

 middle annulus laterally and partly bears the parapodia. Middle 

 annulus, though never enlarged, is frequently conspicuous by reason 

 of its paler color. Pygidium unknown. 



Parapodia characteristic, the anterior short and deep, the posterior 

 longer and more cylindrical. First two situated high by the sides 

 of the mouth with the notopodium much reduced and notocirrus 

 totally lacking, consequently consisting of a neuropodium bearing a 

 short, rounded postsetal lip and a longer acute asymmetrical presetal 

 lip. Remaining parapodia (PI. XXI, figs. 158, 159) all biramous, 

 the postsetal lip short, broad, and undivided, broadly rounded, often 

 slightly emarginated on middle segments. Presetal lip deeply cleft 



