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Show 442 DR. J. D. MACDONALD ON A NEW CIRRIPED. [June 24, The palps (d) consist of a base and a simple oral terminal segment, with a brush of hairs at its extremity. The mandibles (e) present six prominent teeth, diminishing in size from before backwards-the sixth or apical tooth being notched, so as to give the indication of a seventh. The maxillae (f) support four or five principal conical points, or teeth, upon a slightly oblique but straight edge. The external maxillee (g) are quite membranous, of rhomboidal shape with rounded angles, setaceous on their inner surface, and capable of meeting together below the maxillee, so as to answer the purpose of a labium. The branches of the first pair of cirri (h) are richly bristled, and nearly of equal length and thickness. Assuming this little cirriped to form the type of a new genus, it may be named Parodotepas* neptuni, with the following generic characters, subject, of course, to such revision as may be ultimately found necessary :- Valves five, approximate, transparent in their general extent, but strengthened by the deposit of shelly matter, after the manner of the rudimentary valves of Dichelaspis, without, however, overlapping each other, as they are circumscribed by their respective plates. Carinae not extending beyond the base of the terga, and meeting the scuta in a straight longitudinal line. Mandibles with six teeth, gradually decreasing in size from before backwards; the sixth or apical tooth notched, giving an indication of a seventh. Maxillee supporting about five principal conical points, or teeth, upon an oblique but straight border. Anterior and posterior ramus of the first cirri nearly equal in length and breadth, and well clothed with hairs. In a subsequent cruise to Nandi Bay, Vanua Levu, Feejee, I met with a second little pedunculated cirriped, parasitic upon another swimming crab; but I regret to say that, although I made rough drawings of the oral organs and one or two of the cirri (see the woodcut, p. 443), I did not think it worth while to compare the capitulum with that of the species above described; but, as far as I can remember, it presented very similar characters. The palps (a) presented an oval extremity crested with hairs; and the mandibles (b) were four- or five-toothed, the two or three terminal ones being subdivided irregularly. The maxillae (c) were comparatively short, and furnished with numerous points upon a slightly convex border, the two or three outer ones being separated from the rest by a shallow notch. The external maxillae (d) were small, and closely beset with long hairs upon their inner surface. The anterior branch of the first pair of cirri (e) was very short as compared with the posterior, the segments of both being armed with transverse rows of hairs in front, but quite nude posteriorly. If this inequality in the size of the two branches of the first cirrus be not of generic importance, it is probable that the species may be referable to the genus Dichelaspis. Some future inquirer may be able * n apneas, transition ; the specific name neptuni expresses the habitat. |
