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Family Leodicidal

plate, somites, fig, pigment and mm

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FAMILY LEODICIDAL Lumbrinerels eingulata n. sv.

An unusually small representative of this genus, the largest individuals being not over 40 mm. long with a prostomial width of 1 mm. The type after preservation was 37 mm. long and had 98 somites.

The prostomium when extended is broadly rounded, its length a little greater than its breadth (plate 2, fig. 7). There are no eyes, but some individuals have two relatively rather large pigment patches near the anterior border. The head, both dorsally and ventrally, is thickly studded with minute tuber cles, clearly seen only under rather high magnification. These appear dark by transmitted, white by reflected light.

The first two somites are about equal in size (with tubercles similar to those on the prostomium), and each marked dorsally by two prominent bands of pigment spots. On later somites the tubercles are present, but except on the last two somites are less numerous than anteriorly. Anteriorly the somites behind the second have a narrow transverse band of pigment spots with occa sionally much fainter bands at the margins of the tuberculated areas; they disappear entirely after the thirtieth somite. Ten or more of the most pos terior somites have prominent ventral pigment patches which fuse to form a line that is wider in the center of each somite than intersegmentally. The body is very soft and easily broken, and secretes large amounts of mucus when put in clean water. There are two pairs of stout, unequal anal cirri.

The parapodia are similar throughout the body. Each (plate 2, fig. 8) has an anterior and a posterior lobe, the latter much the larger. I was unable to find any aciculte. Setae of two kinds. In the anterior somites the most prominent are the winged variety (plate 2, fig. 9); each has two winged pro cesses and its axis is drawn out in an acute point, often much longer than in the one figured. At the sixteenth parapod in two specimens I examined (I am not sure that this is a constant position) the winged seta disappear and hooded forms (plate 2, fig. 10) take their place. In most cases it seemed as if only winged ones were present in anterior somites, but in the fifth para podium of one specimen was one hooded form which barely protruded from the surface.

The maxilla) (plate 2, fig. 11) are dark in color. The base is roughly tri angular, very dark brown, with lighter margins. Basal portion of forceps rather broad and long, extending fully half the length, terminal portion slender and curved. A dark-brown pigment covers the terminal portion and con tinues as a dark margin along the inner edge of the basal portion, the remain der of the forceps being much lighter in color. The large paired plates have each 5 large, dark-brown teeth, the remainder being colored like the lighter part of the forceps. Of the two pairs of distal paired plates, the first has 3 teeth, the second 2; each is continued laterally into a chitinous plate dotted with black. The left-hand plates in the figure have been turned over. The mandibles are very delicate and difficult to separate from the maxillae; they are nearly transparent, the only definite pigment being a dark spot on each near its outer anterior angle. The terminal beveled plate is not divided in the middle line. (Plate 2, fig. 12) Collected at the Tortugas, where only 3 individuals were found, living in the crevices of broken coral, which make up a coarse gravel on parts of the bottom about 12 miles south of Loggerhead Key. They were common in Bermuda, living in the crevices of the porous surface of coral rocks, just below low-water mark, and some were found in a sponge. The type is from Bermuda.

Type in the American Museum of Natural History.

Marpkysa •iridis a. sp.

The type specimen, preserved and much contracted, was 100 mm. long, 2.5 mm. broad at peristomium, and 5 mm. broad at point of greatest width, which was at middle of body. It had approximately 200 somites.

In life the head and first somite are of a decidedly greenish color; remainder of body colored only by the blood seen through body-wall and gills. The head is distinctly bibbed and capable of considerable changes of form (plate 2, fig. 13). The tentacles are slender, colorless, and extend to the third somite. In life the eyes are prominent, but become less so after preservation. In preserved material the body as far as the ninth somite is very iridescent, but behind this it is of a uniform grayish brown.

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