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Family Phyllodocida

somite, surface, parapodium and rounded

FAMILY PHYLLODOCIDA. Phyllodoce tortugie a. sp.

Body of type 120 mm. long, of more than 200 somites. Prostomium 1.5 mm. in diameter, rather longer than broad (plate 2, fig. 4). Anterior and lateral margins of prostomium rounded, but posterior half of lateral mar gin nearly straight. Posterior margin deeply incised, and a nuchal papilla projects into this incision. Four subequal tentacles having rounded ends, their length not more than one-fourth that of head. Eyes one pair, large, black.

The ceratophores of all tentacular cirri are prominent, those of the dorsal ones on somite 2 being the longest. The terminal joint of the first cirrus and the ventral one of the second pair are very similar in form and size, while the dorsal one on somite 2 is the longest, reaching to the ninth somite; cirrus of third somite intermediate in length between the other two.

The partially protuded proboscis bears on either side a dense arrangement of disk-like papilla, a median dorsal and ventral region being free from them.

The greatest width of the body, about 3 mm., was reached at somite 18. The anal cirri were much distorted in the type. On a cotype which was regen erating the posterior end, there was a single anal cirrus similar in form to the tentacular cirri, but much smaller.

Notocirri of anterior region obovate and inconspicuous in preserved material, standing well out from surface of body; they are larger and more conspicuous toward the middle of the body, and decidedly overlap one another, though at no time do they cover any very large part of the surface.

The parapodia (plate 2, fig. 5, of the tenth) with a bifid anterior lip, the posterior lip shorter and rounded (shown in dotted line in figure). A single acicula extends through the middle of the parapodium, the latter bearing on the end a row of about 10 compound seta. The notocirrus is carried on a very stout ceratophore. The neurocirrus is on the postero-ventral face of the parapodium, its lower margin broadly rounded, bending up to form an acute angle with the straight upper margin. Later parapodia are similar to this in every detail, with the possible exception of a slight increase in the size of the notocirrus.

Seta from tenth parapodium (plate 2, fig. 6) slender with the apex of the basal joint covered with spines on its convex surface; terminal joint long, slender, fine-pointed, with row of minute teeth along the concave surface. The seta of later somites resemble these in form, but the basal joint becomes longer, causing the seta to protrude considerably beyond the parapodium.

Type and cotype in American Museum of Natural History.

The type was collected at Loggerhead Key in the Dry Tortugas in 1914. The cotype was obtained by dredging about 10 miles south of Loggerhead in 1915.