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 8. Macrocypria angusta, G. O. Sars. 



(PI. XXVIII). 



Bairdia angusta, G. O. S;irs, Oversigt af Norges marine Ostracoder, p. 22. 

 Syn : Macrocypris angusta, G. O. Sars. 



Specific Characters. Female. Shell, seen laterally, of a very narrow 

 and elongated form, almost lanceolate in outline, greatest height a little in 

 front of the middle and scarcely exceeding */3 of the length, dorsal margin 

 evenly arched, though exhibiting near the posterior corner of the shell a slight 

 concavity, ventral margin distinctly sinuated in front of the middle and exhib- 

 iting a slight tendency to convexity behind, anterior extremity obliquely pro- 

 duced and terminating below in a sharp dentiform corner, posterior extremity 

 rather more exerted and produced to a narrow somewhat cultrate prominence; 

 seen dorsally, narrow fusiform in outline, greatest width about in the middle 

 and not attaining Vs of the length, both extremities sharply pointed. Valves, 

 as in Macrocypris, conspicuously unequal, rendering the hing-line somewhat 

 flexuous, surface smooth and polished, only clothed with scattered fine hairs, 

 marginal chitinised zone rather broad at each extremity and crossed by fine 

 striae. Anterior antennae with the basal part only slightly dilated, 1st joint of 

 terminal part unusually prolonged, attaining the length of the 3 remaining 

 joints combined, apical setae rather slender. Posterior antennae with the terminal 

 part almost twice the length of the basal one, and having 'the 2nd joint con- 

 siderably longer than the 1st; apical claws comparatively short. Left caudal 

 ramus simply lanceolate and scarcely more than Va as long as the right, which 

 is considerably produced and terminates in a sharp somewhat hamate point. 



Male, as usual, of somewhat smaller size than female, but resembling it 

 closely in the shape of the shell. Prehensile palps of maxillipeds with the pro- 

 podus rather narrow, oblong in shape and armed at the end inside with 2 

 short spines, dactylus abruptly bent at the base. Copulative appendages pro- 

 nouncedly club-shaped, being attached to the body by a narrow neck, and 

 almost globularly dilated in their outer part, each appendage sending off inside 

 2 apparently mobile beak-like processes, which give the appendage a certain 

 resemblance to a birds head. 



Colour in both sexes pure white. 



Length of adult female amounting to 1.80 mm. 



Remarks. The above-described form cannot be confounded with any of the 

 other Cypridae, exhibiting, as it doe's, a very characteristic outward appearance. 

 The peculiar asymmetry of the caudal rami, at first overlooked, is a quite 

 unique character not found, a far as I know, in any other Ostracoda. 



