25 



view of the carapace the upper border of the cardiac region appears a Httle concave, that of 

 the gastric slightly convex, and the upper margin of the rostrum runs obliquely downward, 

 while the tip projects horizontally forward. 



The eyes do not project beyond the anterior margin of the carapace, the corneae are 

 half as broad as long. The antennular peduncle measures about one-third the length of the 

 carapace, the 2°'^ joint is as long as the visible part of the i^' and a little longer chan the y^; 

 the anterior border both of the i^' and of the 2"'' article is frinofed with long- feathered setae. 

 The stylocerite, acuminate and with the apex slightly turned outward, extends a little beyond 

 the basal article; the flagella do not seem to agree with Coutiere's figure 120 (I.e. p. 133). 



Basicerite with a small spine on the anterior border of the lower surface, antennal 

 peduncle reaching to the distal extremity of the 2°<i joint of the antennular stalk; according to 

 Stimpson the basicerite should be unarmed. The rounded tip of the lamella of the scaphocerite 

 reaches a little beyond the distal extremity of 2°*^ antennular article, the terminal spine, that 

 projects rather far beyond the lamella, extends almost to the tip of the antennular peduncle, 

 the outer margin, finally, is slightly concave. 



Telson 0,98 mm. long, lo-times as long as the distance between the posterolateral 

 angles, while the width at the base, 0,46 mm., is almost half the length; of the two spines 

 at the postero-lateral angles the longer inner one is as long as the distance between these 

 angles, the outer almost half as long as the inner. The anterior pair of dorso-lateral spinules 

 are implanted just on the middle of the telson, the posterior pair a little farther distant from 

 the posterior margin than from the anterior pair, these spinules are 0,085 mm. long. The 

 posterior margin of the telson agrees with the figure 396 in Coutiere's work (I.e. p. 314). 



The outer uropod reaches as far backward as the longer terminal spines of the telson, 

 the inner is but a trifle shorter. 



The nearly straight lower border of the pleura of the 5"^ somite terminates in a small 

 acute tooth, while the tooth at the end of the lower border of the 6^^ is much larger. 



External maxillipeds a little longer than the carpocerite, reaching the middle of 3"^'' 

 antennular article, terminal joint 2Y3-times as long as the penultimate. The two peraeopods of the 

 1^' pair (Fig. 12 a) are equal, in one of them the fingers are a trifle shorter than in the other, 

 but the difference is very small; Stimpson describes them as "fere aequales", while according 

 to Coutiere's figures they should be rather very unequal. Merus obtuse at the distal extremity, 

 nowhere acute. Carpus very short, the anterior surface widened, concave. Chelae 2,5 mm. long, 

 nearly as long as the carapace, rostrum included, 4-times as long as the height of the palm. 

 According to Coutiere's figure 228 (I.e. p. 193) the compressed fingers should in Alpheopsis 

 trispinosa be one-fourth .shorter than the palm, according to the figure 230, however, 

 one-third. In the specimen from Stat. 166 the fingers are hardly half as long as the 

 palm, in one chela the fingers are 0,8 mm. and the palm 1,7 mm. long, in the other 

 0,76 mm. and 1,7 mm., so that they are shorter than in Coutiere's species. The T-shaped 

 groove on the palm agrees with the description and the figures of the french author, the 

 longitudinal groove extends to the proximal third of the palm, the notch near the articulation 

 of the fingers appears, however, on the outer side hardly deeper than on the inner and the 



SIBOGA-EXPEDITIE XXXIX a*. 4 



