634 ON CRUSTACEA BROUGHT BY DR WILLEY FROM THE SOUTH SEAS. 



CiROLANA MINUTA, H. J. Hansen. 



1890. Cirolana minuta, Hansen, Cirolanidae, p. Ill (K. D. Vid. Selsk. Skr. p. 347), 

 pi. 3, fig. 5—5 d, pi. 4, fig. 1—1/. 



The frontal plate has an acuminate horn at its base, a distinctive character 

 but not especially easy to observe. Hansen describes and figures the peduncle of 

 the first antennae as two-jointed. In the specimen here referred to his species 

 there are two short joints followed by a long one, the first joint the thickest ; the 

 flagellum has nine joints, the last two very small. In the second antennae one of 

 the flagella has seventeen joints, the other twenty-one ; Hansen gives seventeen or 

 eighteen joints. 



The right mandible has the ujjper tooth of the cutting edge blunt, the next 

 triangular, short, the lowest triangular, long; in the left mandible the blunt upper 

 and sharp lower tooth are both small, with a rather long low obscurely bipartite 

 ridge between them. The other mouth-organs are in close agreement \vitli Hansen's 

 figures. The vibrating plate of the second joint of the maxillipeds has only about 

 eight setae on the outer margin, and they are rather coarsely plumose. The large 

 size of the fifth joint is characteristic. 



In this species the second joint of the sixth and seventh paraeopods is not 

 adorned with long plumose setae. 



In the uropods the inner ramus is longer and much broader than the outer ; 

 both have the apex bifid. Under slight pressure the inner ramus reaches very 

 distinctly beyond the last caudal segment, whereas Hansen speaks of that segment 

 as reaching a very little beyond the uropods, no doubt indicating the appearance without 

 pressure. 



Length of specimen, 3"75 nan. 



Habitat. Sandal Bay, Lifu, Loyalty Islands. 



The possibilit}' is open that this species may be identical with the incompletel}' 

 described Cirolana latistylis, Dana. 



, Hansenolaxa, n. g. 



Mouth-organs as in Cirolana. Head wider in front than behind. Segments of 

 pleon widening to the fourth, which conceals the angles of the fifth. First gnathopods 

 complexly subchelate, much larger than an}- of the following limbs of the peraeon. 

 All the pleopods with the peduncle broader than long and with both rami mem- 

 branaceous, the peduncle of the first pair with eight uncinate spines on the inner 

 mai'gin. 



As well from Cirolana as fi'om its neighbouring genera Conilera and Euri/dice 

 the new genus is distinguished in a marked manner by the character of the first 

 limbs of the peraeon. Among the species of Cirolana the aberrant C. sphaeromi- 

 formis, Hansen, makes the nearest approach to the new genus by the general shape 

 and some peculiarities of the head and pleon. 



