4IO 



The female from Stat. 282 is 19,5 mm. long, the two other specimens 16 mm. Rostrum 

 acute, projecting straightly forward and just reaching beyond the i*' antennular article; as broad 

 at its base as it is long, the oblique lateral margins of the rostrum make obtuse angles with the 

 frontal margin that runs, from the rostrum, at first transversely, but soon curves backward and 

 downward; the orbital region projects more forward than in most other species, for just half 

 the first antennular article is covered by it. The rostrum is sharply carina te above and 

 this narrow, linear, compressed and prominent carina runs backward, in 

 the adult female, to beyond the posterior third of the carapace, while it 

 is slicrhtly shorter in the two other specimens; the furrows by which the rounded and unarmed, 

 orbital hoods are separated from the rostral carina, are rather broad and widen anteriorly, 

 nearly as in A. Boiivieri var. Hzdulensis (Coutiere, Alpheidae Maid, and Laccad. Archip. 1905, 

 fig. 46). Gastric and cardiac regions coarsely punctate. 



Like in A. Arethnsa, the abdominal pleura show a different form in the male and 

 in the female. In the male they are produced inferiorly to an angle, subacute on the 1^' 

 and the 2""^, but very acute on the four posterior, w hile the pi eur a of the 

 2"=^ are cordiform; in the female, however, the i^' and the 2"'^ are much broader, with 

 the infero-posterior angle obtuse and with the lower margin of the 2"*^ slightly concave; the 

 two followino- are not triangular as in the male, but their posterior margin is rounded, conve.x 

 and their lower margin is obtuse, the 5"^ and especially the 6"' nearly agree with those of the 

 male. The telson is 3-times as long as its posterior margin is broad and the latter just half 

 as broad as the oreatest width; between the two pairs of spinules that are rather large, 0,22 mm. 

 long, about one-tenth the length of the telson, the upper surface appears broadly grooved 

 from the anterior to the posterior margin, but the groove is rather shallow. Basal joint of 

 the uropods that are but little longer than the telson, armed with two acute spines. Abdomen 

 coarsely, though rather sparsely punctate. 



Second antennular article 2,5-times as long as thick, about twice as long as the visible 

 part of the first, third article little longer than that visible part; pointed tip of the stylocerite 

 reaching to the end of first article. 



Spinule on the basicerite extremely small, 0,06mm. long. Carpocerite very little 

 lono-er than the antennular peduncle and as long as the scaphocerite ; outer margin of the latter 

 very concave and the terminal spine that is turned outward, reaches backward to the distal 

 third of second antennular article ; the terminal spine projects far beyond the blade, that reaches 

 to the middle of the third article. 



External maxillipeds reaching to the end of second antennular article. 

 Merus of the large cheliped of the adult female 4-times as long as broad in the middle, 

 upper margin somewhat uneven, unarmed at the apex, infero-e.xternal margin also slightly uneven ; 

 the infero-internal margin bears along its whole length 10 or 11 rounded tubercles and 

 a small acute tooth near the apex. Chela as long as the carapace, 2,5-times as long 

 as the palm is high, fingers hardly half as long as the palm, the total length of the chela 

 beino- in proportion to that of the fingers as 10:3; the fingers are much less high than the 

 palm, their height being in proportion to that of the palm as 2:3. The upper margin of the 



278 



