(15) 



at tip. The lower angle bears a long simple bristle. Mandibular palpus 

 two-jointed, second joint with three long terminal hairs and a shorter spine 

 attached at basal third of anterior margin, jointed at base and directed 

 towards tip of joint, like a dactyl. The maxilla and maxillary palpus are 

 scarcely to be distinguished from those of C. stapliylinus. 



The first maxillipeds are three lobed, the outer lobe constituting a long, 

 strong claw. The second and third are about one-third as long as the first, 

 and bear each one strong simple spine and one weak branched hair. The 

 inner lobe is widest, about two-thirds as wide as long. The dactyl of the 

 posterior maxilliped is spinous on its inner edge, and the same edge of the 

 hand is ciliate and bears a short, stout, sparingly plumose bristle at its base, 

 just beyond the tip of the closed dactyl. The width of this joint (the second) 

 is nearly half its length. 



Basal joint of inner ramus of first pair of legs nearly or quite as long as 

 outer ramus, the second wider but only half as long as the third, and obliquely 

 truncate. Inner ramus of third pair of legs in male is three-jointed, the 

 outer two-jointed, chelate. The finger is ovate, truncate, terminating in 

 two long plumose hairs. The dactyl is linear, curved at base, and twice as 

 long as finger. The inner ramus of the faurth pair of legs is about half as 

 long as outer, two-jointed, basal joint short, terminal joint about as long as 

 middle joint of outer ramus. The Ji/th pair 0/ If-gs is best developed in the 

 female. In the male the length is not over one-third the width. The basal 

 portion bears three plumose hairs on its very broadly rounded anterior mar- 

 gin, of which the innermost is longest. The outer plate is nearly orbicular 

 and bears five spines on its terminal margin, of which the second from the 

 internal angle is the longest. Genital plates found in male at posterior 

 border of first abdominal segment, beneath, are short, slightly expanded in- 

 ternally, with internal angles rounded, and externally bear three sub-equal 

 bristles, jointed at base, the inner largest and strongest and semi-plumose. 

 The antennae of the female are eight-jointed, extending backward to the 

 first free segment. The basal joint of the Ji/th pair of legs is sub-elliptical 

 in outline, with the basal half produced externally into a broad, triangular 

 process which bears the second joint on its posterior margin. The free end 

 of the basal joint bears six large plumose bristles of which the inner is 

 longest. The greatest width of the joint is nearly equal to its greatest 

 length. The second or outer joint is ovate, sub-truncate, spined on each 

 margin, and bears four plumose bristles at tip and one at the middle of its 

 outer margin. Its length is about twice its breadth. Same habitat as the 

 following : 



Diaptomus sanguineus, Forbes. This species difiers in some slight re- 

 spects from the genus to which I have assigned it, as characterized by Claus, 

 (Die Frei Lebeiiden C<>pepodeii) but not sufficiently to constitute it a new 

 genus. In the male the fifteenth to eighteenth joints of the right antenna 

 are thickened, the teeth of the mandible are not at all emarginate, the first 

 joint of the terminal portion of the lower maxilliped is smaller than the 

 others, and the right foot of the fifth pair in the male wants the inner 

 ramus, which is perhaps represented by an immovable blunt spine at the 



