682 Bkady and Noerun — Monograph of the Ilan'ne and Freshwater Ostracodn 



unguis.* The copulating appendages (fig. 15) have each lobe terminating in a 

 large hook-shaped claw; caudal laminse (fig. 15) with five rather long ungues, 

 which gradually increase in length distally, the last, however, much longer than 

 the penultimate ; they are all strongly ciliated at the edge. 



Habitat. — Dredged in 112 fathoms, off Valentia, Ireland, in 1870 (A. M. N.) 

 Birterbuy Bay, Ireland, 1871 (A. M. N. and D. Robertson). 



Fam.— HALOCYPRID-ffi. 



Valves sub-equal, very thin and flexible, composed of two tunics, which are 

 scarcely adherent except at the edges ; hinge-margin straight, almost, or quite, 

 edentulous ; anterior extremity produced more or less into a beak-like prominence 

 with a subjacent sinus. Eyes wanting, or present only in an abnormal condition. 

 Projected forwards in the median line between the antennules is a frontal tentacle 

 usually clubbed at the extremity."]" Antennules dissimilar in the two sexes ; in the 

 female weak, indistinctly jointed, immobile and bearing a fascicle of sensory 

 setse; in the male larger, distinctly jointed, mobile, and with elongated setas. 

 Antennae natatory and, as in Cypridinidas, bearing a secondary branch, which in 

 the male has a prehensile appendage. Mandibles well developed, biting jjlate 

 dilated and toothed at the apex : palp large, four-jointed, geniculated, basal joint 

 produced and forming a large chewing dentated lobe in contact with the biting 

 apex of the mandible ; terminal joints bearing curved setfe or spines. Two pairs of 

 maxillae. Two pairs of feet, the first jDair the larger and dissimilar in the two 

 sexes ; second pair very small, both paii's having branchial laminae attached near 

 the base. Caudal laminae short and clawed on the posterior margin. Copulatory 

 organ of the male single, sinistral. 



Sub-fam. — Conclicecinae. 



Shell elongated, its length usually very much greater than its height ; rostral 

 process well developed, and having a well-marked subjacent sinus. Frontal 

 tentacles different in the two sexes ; in the male surrounded by a tentacular circlet 

 which springs from the second joint of the antennule, and ending in a club-shaped, 

 angularly -bent capitulum. Peduncle of the antennules elongated and more massive 

 in the male than in the female ; in the female bearing one long, simple, tei'minal 

 seta and four much shorter sensory filaments which are of equal length ; in the 



* It -will be observed on comparison of our figure and description of the limb, which stand as they 

 were before Miiller's work reached us, that they much more closely accord with the figure of this organ in 

 his Sarsiella Icevis <y , than that of his Sarsiella capsula $ . 



\ "We employ the term " capitulum " for this clubbed extremity. 



