378 TAGE SKOOSBERG 



anterior ones and have long, soft hairs, either, as in the case of those situated farthest back, 

 right out to their points, or else only along the greater part of their length; in the last- 

 mentioned case they have short hairs distally. Most or all the anterior bristles have long, stiff 

 secondary bristles at the middle and are moderately strongly or finely pectinated distally. 

 The transition fi-om the anterior to the posterior type of bristle is gradual. 



Seventh limb: — This shows weak sexual dimorphism (G. W. Mi5LLER states, 

 1912, p. 25, that this limb is similar in both sexes). 



Female: — The number of cleaning bristles varies somewhat, from eight to over 

 forty were observed. Some of these are situated close together distally, the others are placed 

 irregularly along the distal part of the limb; with regard to the position of the latter it is to be 

 noted that it is only exceedingly seldom that there is more than one bristle on the same side 

 of the same joint. The end comb consists of a rather slight or a moderate number of teeth (from 

 about seven to nearly twenty), which, unlike in most forms of the sub-family Cypridininae, 

 cannot be divided into proximal and distal teeth. Dorsally near the end comb the wall of the 

 limb becomes somewhat thicker and is furnished with a varying number of chitinous pegs; in 

 addition the wall is somewhat concave here, the depth of the concavity varying. The dorsal 

 and ventral walls of the concavity are not moveably joined to each other, nor is there any special 

 adductor such as is found in many of the forms belonging to the sub-family Cijpridininae. 

 \^^lether, in spite of this, the end comb can be pressed in towards the dorsal edge of the concavity 

 I have not been able to decide, as I have had only preserved material of these forms at my 

 disposal. I wish merely to state here that among the material investigated by me I never found 

 any specimen with its end comb pressed inwards, although I had very abundant material. 



Male: — Differs from that of the female especially by the cleaning bristles having 

 a somewhat, though only very slightly, smaller number of bells and by a slight reduction of 

 the end comb. 



Penis: — This is small, but has a rather well-developed muscular system, Distally 

 it is divided into two rather short, ciuved processes, both having a few bristles distally (= the 

 exopodite and endopodite of an original biramous limb?). It is rather weakly chitinized and 

 has no strongly thickened lists. 



Furca: — This has weak (or is sometimes quite without?) sexual dimorphism. 

 CI. W. MULLER states, 1912, p. 25, that in this genus this organ is quite alike in males and females. 



Female: — The lamellae seem to be subject to rather slight variation with regard 

 to type; they are moderately elongated. From six to fifteen, in most cases from nine to twelve, 

 furcal claws have been observed; the number of claws seems to be subject to some, though 

 only a rather slight, variation in several species of this genus. In a number of species main 

 claws and secondary claws can be distinguished, in others a division of this kind cannot be 

 carried out; all the claws are well defined from the lamella. On all the species of this genus that 

 were investigated by me the equipment of the claws is about as follows: The first claw has two 

 rows of smooth secondary teeth; the inner row, which is displaced somewhat dorsally, consists 

 for the most part of powerful teeth pointing distally , the teeth in the outer row are either 

 powerful or there is an irregular alternation between powerful and weak ones — in this respect 



