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

;;662 COLLECTIONS PEOM THE WESTEEN INDIAN OCEAN.Islands, and may be identical with it ; but differs from his brief descriptionin some minor points, e.g. in the absence of the smaUspiuules at the base of the third and fourth legs.4. Alpheus minor, var. neptunus, Dana.Specimens of this species, whose synonyms and distribution havebeen referred to at p. 288 of this E-eport, are in the collection fromDarros Island, 22 fms. (No. 185), He des Noufs, 15 fms. (No. 187),and Glorioso Islands, 7-10 fms. (No. 219).5. Pontonia? brevirostris. (Plate LI. fig. B.)The body of this species is shaped nearly as in P. tridacnm (Peters).The rostrum is very small, not at all laterally compressed ; vieweddorsally it is triangular and acute, and scarcely prolonged beyondthe bases of the eye-peduncles ; the anterior margin of the carapace,near to the antero-lateral angles, is armed with a spine ; the lateralmargins of the second to fifth postabdominal segments are obtuselyrounded, those of the sixth segment posteriorly spiniform and acutethe terminal segment is subtriangulate, with the apex subacute(broader and more rounded in the adult female), and bears on itsdorsal surface two strong spines near to each lateral margin. Theeye-peduncles are subcylindrical, thick, and project laterally. Thefirst exposed joint of the anteunulary peduncles is flattened and considerablydilated, and has two spines on its outer margin, of whichone is at the extcro-distal angle of the joint ; the next joint is veryshort, the terminal joint longer ; the outermost of the two shortflagella is thickened and shortly bipartite. The antennie are insertedbeneath and outside of the antennnles, and their shortpeduncles in a dorsal view are hidden by the antennal scales, whichare large, ovate, and distally ciliated, and prolonged beyond thedistal end of the peduncles and the antennnles. The slender mandiblesarc without a palpus ; the outer maxillipedes are subpediform,with the antepenultimate joints but slightly thicker and a littlelonger than the two terminal joints taken together. The anteriorlegs are slender and unarmed, with merus and carpus of about equallength, and each about as long as the palm and fingers taken together ;the palm is not dilated, and the fingers are not denticulated on theirinner margins. The second legs (in the specimens examined) arebut moderately thickened and of nearly equal size ; ischium, merus,and carpus of about equal length, but the carpus somewhat thicker ;palm longer than the carpus, smooth and rounded, scarcely compressed; fingers about as long as palm, meeting along their innermargins, which are not denticulated. Ambulatory legs slender,with the penultimate joints about twice as long as the precedingdactyli styliform and acute. The rami of the uropoda are ovate andciliated, and the outermost has a small spinule near to the distal endof its outer margin. Colour (in spiritj reddish yellow. The exactdimensions of the larger specimen, owing to its imperfect condition,