153 



with the dactylus very long and abruptly curved in the middle, tip minutely 

 hamate. 



Body in both sexes semipellucid, of a whitish hue; ovarial tubes and 

 ovisacs in female of an opaque pure white colour; eye bright red. 



Length of adult female amounting to 1.50 mm.; that of male scarcely 

 -attaining 1 mm. 



Remarks. This form has been very carefully described and figured by 

 Thorell in his above-mentioned paper, and, as it is that species which is placed 

 at the head, it ought to be regarded as the type of the present genus. 



Occurrence. I have taken this form from the branchial cavity of vari- 

 ous Ascidians captured on the south and west coasts of Norway, most 

 frequently perhaps from that of Corella paralellogramma. It is generally found 

 attached between the lamellae of the branchial sac; but it may easily change its 

 place. When detached, it swims about rn the usual cyclopoid manner, though 

 by no means very rapidly. Owing to its pale semipellucid body, it is not 

 easy to detect, except when loaded with the large ovisacs, the opaque white 

 colour of which at once strikes the eye., 



Distribution. Bohuslan (Thorell), British Isles (Scott), ? coast of France 

 (Canu), Mediterranean (Delia Valle). 



80. Lichomolgus forficula, Thorell. 



(PI. LXXXIV). 

 Lichomolgus forficula, Thorell, 1. c. p. 73, Pi. XII, XIII: 19. 



Specific Characters. Female. Body comparatively more slender than 

 in the type species, with the anterior division more regularly oval in outline, 

 the greatest width occurring at about the middle, 1st trunk-segment very distinctly 

 defined from the cephalon; last segment small, though scarcely narrower than 

 the genital segment. Tail very slender, even exceeding in length the anterior 

 division; genital segment slightly dilated in front of the middle, with the 

 anterior part not sharply marked off from the posterior; anal segment very 

 long and narrow, attaining half the length of the preceding part of the tail, 

 and more than twice as long as it is broad. Caudal rami exceedingly slender 

 and elongated, considerably exceeding half the length of the remainder 

 of the tail, and somewhat bent in front of the middle, carrying at this place 

 dorsally 2 juxtaposed delicate bristles, one of them apparently answering to 

 the seta of the outer edge in L. albens; distal part of the rami very narrow 

 and attenuated, curving generally slightly outwards; apical setae, as in L. albens, 



