

10g6 CRUSTACEA. 



out setae. In the male they are long and straight, and extend forward, 

 reaching as far as the mouth, or even beyond. The right terminates 

 in an imperfect hand, consisting of a small arcuate thumb, or 

 immoveable finger, and a long subulate finger, at least three times as 

 long as the thumb. The left is two-branched; one branch is a single 

 oblong joint ; the other consists of two long joints, of which the 

 second is long subulate. 



The setse of the antennse of the females are quite similar in different 

 species. The apical are four or five in number, there being two long 

 posterior, of which one is one-third to one-half as long as the antenna, 

 one anterior somewhat shorter, and one or two quite short extending 

 outward. The posterior penult is about as long as anterior apical ; 

 the anterior penult very short. The posterior antepenult is sometimes 

 as long as the joint, in other cases very short; the anterior antepenult 

 very short. Counting from the apex, the fourth, seventh, eleventh, 

 seventeenth, eighteenth, and twenty-first joints are furnished with 

 very long setae, and of these, the setae of the seventeenth and eighteenth 

 joints are bent, and have free motion in different directions; the 

 others are directed straight forward in parallel lines, except the 

 posterior apical, which point straight backward. 



The species of this genus, though few in number, are very exten- 

 sively distributed in the Atlantic, and but little less so in the Pacific 

 Ocean. 



Euchseta, Philippi, Archiv fur Naturgeschichte, ix. 55. In the figures given by 

 Philippi, the mandibular palpus is separated from the rest of the mandible, and called a 

 "kaufuss," or maxilla-foot. His fig. 5 d, is properly the mandibular palpus; 5 c, the 

 maxilla; 5 e, the maxilliped; 5/, the foot of first pair. 



Euchirus, Dana, Amer. J. Sci. [2], i. 228, Euchseta ; Proc. Amer. Acad, ii., 20, where 

 the following new species are briefly described by the author. 



EuCH^ETA COMMUNIS. 



CepJialotJtorax nudus, 4-articidatus, postich obtusus. Feminse : — Antenna 

 anticce, corpore vix breviores, setis panels remotis prcelongis, recits, et 

 aliis duabusflexis longissimis, apicalibus prcelongis, posticd antepenul- 

 timd fere articuli longitudine. Setce caudales rectce, secundd scepius 

 corporis longitudine. Ova cwrulea. Maris : — Antennas antkw corpore 

 paulo breviores, angulo levissimd flexo?, setis brevibus, paucis, articulum 

 apicalem vix superantibus. Seto3 caudales abdominis longitudine. 



