81 



reduced in size, being scarcely half as long as the distal one and almost per- 

 fectly straight. Copulative appendages comparatively smaller than in C. rostrata 

 and slightly differing in shape, lower terminal lappet somewhat bilobed at the end. 



Colour whitish, semipellucid, with a fainte yellow tinge. 



Length of adult female scarcely exceeding 0.92 mm.; that of male 

 about 1 mm. 



Remarks. -The present form is closely allied to C. rostrata, and seems 

 indeed often to have been confounded with that species. It is however rather 

 inferior in size, and has the shell, at least in female, conspicuously shorter 

 and stouter. Dr. Hartwig has moreover called attention to an easely observable 

 difference in the structure of the caudal rami in both sexes. 



Occurrence. I have found this form not unfrequently in similar localities 

 to those in which C. rostrata occurs, but only in the early part of the summer. 



Distribution. -Sweden (Ekman), Germany (Hartwig), Switzerland (Kaufmann). 



20. Candona stagnalis, G. O. Sars. 



(PI. XXXVIIi; fig. 2). 

 Candona stagnalis, G. O. Sars, Oversigt af Norges Crustaceer II, p. 65. 



Syn: Candona Zenkeri, G. 0. Sars. 

 rara, G. W. Miiller. 

 qvadrata, Aim. 



Specific Characters. Female. Shell, seen laterally, oblong subreniform 

 in shape, greatest height behind and scarcely exceeding half the length, dorsal 

 margin straight and nearly horizontal, joining the posterior edge by an abrupt, 

 almost angular bend, ventral margin distinctly sinuated, anterior extremity 

 obliquely rounded, posterior much broader and obtusely blunted, forming 

 below a rather conspicuous bowed expansion; seen dorsally, narrow oblong 

 in outline, with the greatest width about equal to -k of the length, both 

 extremities obtusely pointed. Surface of valves smooth, without any obvious 

 sculpture, and clothed at each extremity with comparatively short and fine 

 hairs, posterior expansions flanked by a rather broad pellucid border. Posterior 

 legs with the penultimate joint not subdivided, shortest apical seta about the 

 length of the terminal joint and not hamiform curved. Caudal rami com- 

 paratively slender and attenuated, almost straight, apical claws of moderate 

 size and not much unequal, the distal one scarcely exceeding half the length 

 of the ramus, dorsal seta small and attached not far from the end. Genital 

 lobes of unusual size, subquadrate in shape and forming behind an angular 

 corner. 



10 Crustacea. 



