Sliidins (111 iiiiiriiii'. Oslracocis 161 



the greater part of their length with close, fine, stiff, rather long hairs, arranged in shape 

 of feathers. 



Sixth limb: — Forms a comparatively short, lamelliform, very slighth' moveable 

 or sometimes iimnoveable, plate of somewhat varying type, situated ventrally on the body 

 between the mouth and the furca; is apparently never used as a locomotor}- organ. 



Seventh limb: — Originates rather high up on the side of the back of the body. 

 Very elongated and mobile, annelid-like, with very numerous joint-like, ring-shaped chitinou.s 

 stripes (like the structure of the trachea), but with no real division into joints; flattened distally 

 and here armed more or less abundantly with cleaning bristles arranged in a single row along 

 the dorsal and ventral edges of the limb. The cleaning bristles are of about the same 

 type within the whole group, rather powerful, annulated and provided distally with bell-shaped 

 segments, overlapping each other somewhat; these segments become more and more narrow 

 the more distally they are situated, and are armed along the distal edge with a dense series of 

 moderately long, fine, stiff spines. This limb is often fitted at its point with teeth arranged 

 in the shape of a comb. It is absent in males of the genus Sar.si^/ia. 



B r u s h - 1 i k e or g a n: — Is absent almost throughout. FA)r tlu; jjossiblc orcairreuce. 

 of this organ on the penis see p. 76 above. 



Copulatory organ: — Paired, varies a good deal in type; compared with 

 the same organ in other Ostracod groups it is in most cases of a rather simple structure. 

 The vasa deferentia do not pass through it. 



Furca: — Always well developed, large, powerful, with ccjmparatively .short, broad 

 lamelliform rami, always armed with several powerful claws. The posterior part of the dorsum 

 forms a rather strongly chitinized, oval, somewhat spoon-shaped furcal field, which is well 

 defined from the furcal lamellae- and furnished with a well developed muscular system; see 

 (4. \V. MUllrf!, 1894; pi. XXXV, figs. 5 and 11. Proximally to the furcal claws there is no 

 unpaired bristle (such as is found for instance in H a 1 o c y p r i d s and P o 1 y c o p i d s). 



Aliment a r y organs: — Mouth wide, narrowing ra])idly towards the interior. 

 A t r i u m relatively weakly defined. L a b r u m varying in type, sometimes very large, 

 sometimes rather small. Lower lip very small, may be quite absent. P a r a g n a t e s 

 most frequently quite absent, and if developed, small and weak. T he glands of t h e 

 upper lip most frequently developed but very varying in type and development; may be 

 absent. O e s o p h a g u s rather long, most frequently very strongly nuiscular, somewhat 

 varying in type. S t o m a c h large, oval, most frequently without hepatical appendages; 

 surrounded by a layer of pigment cells, outside which is to be found a stratum of wide-nie.shed 

 connective tissue. Rectum very short, opening out in front of the furca. No parts of the 

 digestive organs ever penetrate between the lamellae of the shell. 



Sexual organs: — Male: The testes are paired and consist of two bag- 

 shaped oval bodies situated posteriorly in the body. From each of the testes there runs a rather 

 short, wide canal, vas deferens; the vasa deferentia emerge with a common pore ju.st 

 in front of the anus, i. e. between the two penes; they unite rather near the outer exit; see 

 (!. \V. MOLLRH, 1804, pi. XXXVTII, fig. 30. Female: The r. v a r i e .s, like the teste.s, 



Zooloy. liftlru«, Uppwlii Siippl.-IM, 1. -I 



