2356 CRUSTACEA. 



Caligus gracilis. 



Feminae : — Carapax oblongus, fere ellipticus, discis suctatoriis rotun- 

 datis. Segmentum secundum transversum, brevissimum. Abdomen 

 2-articidatum, segmento antico fere quadrate-, postico angustiore, parce 

 oblongo, posticd truncate*. Styli caudales terminates, paulo oblongi. 

 Furcula ventralis simplex, brachiis diver gentibus, truncatis. Antmnm 

 posticm spina oblongd extus basin munitce. 



Female: — Carapax oblong, nearly elliptical, sucker disks of front 

 round. Second segment transverse, very short. Abdomen two- 

 jointed, the anterior segment broadest, nearly square, the posterior 

 slightly oblong, truncate behind. Caudal stylets terminal, a little 

 oblong. Ventral furcula simple, prongs divergent, truncate. Pos- 

 terior antennae having an oblong stout spine exterior to base. 



Plate 94, fig. 5 a, dorsal view of animal, enlarged ; b, posterior an- 

 tennae ; c, maxilla ; d, second pair of legs. 



Rio Janeiro, from the body of a Serranus. 



Length, one-sixth of an inch. Colourless. Sucker disks a little 

 yellowish and very distinct. 



The first abdominal segment is nearly half as broad as the carapax. 

 The posterior is truncate behind, without the anus prominent, and 

 having the stylets projecting their length beyond the anus. Three 

 plumose setae about as long as the posterior segment, and one or two 

 shorter. 



The posterior antennae very slender towards apex. The corneous 

 spine exterior to its base long and slender, and but slightly curved. 

 On the posterior side of the base there is a very short spine. The 

 maxillae have the spine long and slender. The second pair of feet 

 (f. 5 d) have the finger about half as long as the preceding part. 



The external ovarian tube in the specimen examined was shorter 

 than the body. 



