Report on the zoological collections made in the Indo-Pacific Ocean ...

270 COLLECTIONS FEOM MELANESIA.are slender ; dactyli short, terminating in a small claw. Colour (inthe spirit-specimen) pale reddish yellow, punctulated with darkerred. Length nearly 7 lines (14 millim.), breadth a little over 6 lines(13 millim.) ; length of chelipede about 11 inch (34 millim.).An adult female is in the collection from Thursday Island, obtainedon the beach (No. 167).There is also in the Museum collection a female from Port Curtis,Facing Island, two examples from Torres Straits (./. B. Juices), andtwo from the Samarang ' ' collection, of which one is from Koo-Keang-San.The three distinct spines on the posterior margin of the arm seemto distinguish this form from the P. bellis of Heller, from theNicobars—a species, however, which is only briefly characterized.It is evidently very nearly allied to Petrolistlies ruf/osus (M.-Edwards), to which are referred specimens in the British-Museumcollection from Karachi (KaracJii Museum) and North Australia{Dr. J. M, Elseii), which species, however, has the carapace andchelipedes covered with well-defined pilifcrous crests, and the teethof the anterior margins of the wrists much more regular in formand disposition.14. Petrolisthes annulipes. (Plate XXIX. fig. B.)Petrolistlies auuulipes, White, List Crust, Brit. Miis. p. 63 (1847),deseript. nulla.Carapace moderately convex, scarcely longer than broad, its uppersurface and also that of the chelipedes transversely striated ; thestriae imbricated and fringed on the anterior margins with close-setshort setae ; the front is subtriangulate, moderately prominent,slightly concave above, with the apex rounded or subtruncated, andthe margins usually minutely spinulose ; there is a spine on theupper margin of the orbit just in front of the eye-peduncles ; thesides of the carapace are armed with about six spines, the first ofwhich (when present) is situated just posterior to the outer orbitalangle, the second a little behind it, the third a little within themargin on the front of the branchial region, and the other three onthe sides of the branchial region aud close to one another. Thefirst exposed joint of the antennae is armed with a spine (see fig. h).The ischium- and merus-joints of the outer maxillipedes are transverselystriated and setose, like the carapace ; the last three jointsfringed on their inner margins with very long hairs. The merusjointof the chelipedes is armed with a denticulated lobe at thedistal end of its inner margin ; the carpus or wrist has five denticulatedteeth on its anterior margin, and three or four spines on itsposterior margin ; the palm is armed with a series of minute spinuleson its outer or posterior margin ; the fingers meet along theirinner edges, and have their tips incurved and acute. The ambulatorylegs are somewhat hairy, the merus-joints in the first three pairstransversely striated aud setose, and armed with spinules on their