177 



anterior division, and having the segments finely spinulose at the hind edge ven- 

 trally and laterally. Caudal rami short, being considerably broader than they 

 are long, apical setse normal. Eye inconspicuous. Anterior antennae very slender 

 and attenuated, 8-articulate, 2nd joint much the largest, 4th joint very narrow 

 and twice as long as 3rd, terminal part not quite attaining half the length of the 

 proximal one. Posterior antenna? with the outer ramus about as long as the 

 terminal joint of the inner, middle joint well defined and setiferous. 1st pair of 

 legs with the outer ramus shorter than the 1st joint of the inner, middle joint 

 with a well-developed seta inside, last joint scarcely larger, and armed with 3 

 spines and 2 geniculated setae; inner ramus with the 1st joint very narrow, last 

 , joint more than twice as long as the preceding one, the two together about half the 

 length of the 1st. Natatory legs with the rami nearly equal-sized, and having the 

 normal number of seta3. Last pair of legs very delicate, distal joint regularly 

 oval in form, with the tip obtusely blunted, marginal setse rather small and 6 in 

 number; inner expansion of proximal joint triangular, extending considerably 

 beyond the middle of the distal joint, and produced at the end outside to a small 

 tooth-like projection, inside which a row of 5 setse occur. Ovisacs narrow oblong, 

 with a very limited number of ova. 



Male having the 2nd basal joint of 1st pair of legs armed inside with 2 

 closely-set spines, in front of which is a small knob-like prominence. Inner ramus 

 of 2nd pair of legs transformed in the usual manner. Last pair of legs very 

 small, with the distal joint short and broad, and the inner expansion of the prox- 

 imal joint very slight, tipped with 3 unequal spines. 



Colour whitish. 



Length of adult female 0.54 mm. 



Remarks. This form is chiefly characterised by the very thin and pel- 

 lucid integuments, the unusually slender anterior antennse, and the structure of 

 the 1st and last pairs of legs. No eye could be detected in the living animal. 



Occurrence. Some few specimens of this handsome species were taken last 

 summer in the same locality in which A. productus occurred. 



117. Amphiascus linearis, G. 0. Sars, n. sp. 



(PL CXVII). 



Specific Characters. Female. Body very slender and elongated, linear 

 in form, being of equal width almost throughout. Rostrum less produced than 

 in most other species, narrow lanceolate in shape. Urosome almost attaining the 



