i8o 



Rostrum slender, acuminate, almost reaching to the end of basal antennular article, 

 with the lateral margins regularly curving toward the extra-corneal teeth ; the rostrum appears 

 6-times as long as wide in the middle. Extra-corneal teeth also acute, slightly directed inward, 

 but much shorter than the rostrum, their length being in proportion to that of the rostrum 

 as 5:18. In a lateral view the upper margin of the rostrum seems to be directed obliquely 

 downward, the lower nearly horizontal and the height of the rostrum at its base appears then 

 to be one-third of the length; the extra-corneal teeth are also slightly turned downward. The 

 very black and clearly facetted corneae are entirely covered by the carapace, as in Alph. 

 aeqtcalis Cout., but in a lateral view they prove to reach until to the antero-lateral margin of 

 the carapace. Like in the genus Cheirothrix Sp. Bate the pterygostomian angle is armed 

 with a small, acute tooth or spine, that is directed forward and slightly upward; this 

 spine is barely half as long as the extra-corneal teeth. As far as I am aware, only in two 

 other species of this genus, viz. in Alph. idiocarpiis Cout. from Providence Island and in 

 Alph. consobrinus de Man, the pterygostomian angle is marked by an acute triangular point. 



Pleura of sixth abdominal somite articulate, movable. Telson elongate, 4,7-times as long 

 as the posterior margin is wide, the latter half as wide as the width near the base ; posterior 

 margin as in Alph. trispinosiis (vide: H. Coutiere, Les Alpheidae, 1899, P- 3 Hi Fig- 396), 

 slightly prominent and rounded, with the outer angles not prominent at all ; the longer inner 

 spinules measure about three-fourths the width of the posterior margin, the outer are nearly 

 half as long. The spinules of the upper surface are almost half as long as the posterior margin 

 is wide ; those of the anterior pair, that are nearly as far distant from the lateral margins as 

 from the median line of the telson, are implanted just before the middle, the proportion between 

 the length of the telson and the distance between this pair and the posterior margin being 1,8; 

 the posterior pair is just as far distant from the anterior pair as from the posterior margin. 



Second joint of antennular peduncle one and a half as long as thick, equal to or slightly 

 shorter than the visible part of basal article; third article nearly as long as the second. Outer 

 flagellum consisting of two articles before bifurcation, the first of which is almost twice as 

 long as the second and twice as long as thick, while the second is hardly longer than thick. 

 Olfactory setae well-developed. Inner flagellum composed of a little more than 40 articles. In 

 Alph. trispinosus (Stimps.) on the contrary the second article of the outer flagellum is much 

 longer than the first (H. Coutiere, I.e. p. 133, Fig. 120). Stylocerite slender, acuminate, reaching 

 to the distal fourth part of median antennular article. Infero-internal crest of basal antennular 

 article terminating in an acute spine that extends as far forward as the rostrum. 



Basicerite with an acute spine at the infero-external angle. Carpocerite 4-times as long 

 as thick, about as long, not longer than the antennular peduncle; scale of scaphocerite a 

 little longer than median antennular article, its outer margin straight and terminating in a 

 slender, acute spine, which is twice as long as wide at its base and which, projecting beyond 

 the scale and directed straight forward, extends to the tip of the carpocerite. 



Basal article of external maxillipeds 5, 6-times as long as wide, showing the same width 

 along its whole length ; the following joint measures one-fifth of the preceding and appears 

 twice as long as thick distally; the distal joint, finally, is 3-times as long as the carpus, the 



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