1880.] NATURAL SCIENCES OF PHILADELPHIA. 81 



short penis. The spermatotheca pyriform, about 1.3 mm. long; the 

 ppermatocysta not having one-fourth of the size of the last ; botli 

 empty. The mucous gland whitish and yellow-whitish. 



This seems even externally to differ somewhat from the typical form, 

 of which it nevertheless may prove to be but a variety. Neither Alder 

 and Hancock, nor Meyer and Moebius saw more than eight to (nine) 

 ten external plates on the tongue of Ad. proxima, while this Pacific 

 form always presented fifteen. 



3. Adalaria viresoeas, Bgh., n. sp. Plate X, ti^. \, 5. 



Color virescens. 



Dentes laterales (magni) hamo edentulo ; externi numero 15. 



Hab. Oc. Pacific, septentr. Unalashka. 



Of this species Dall found four specimens at Unalashku, on gravel, 

 in a depth of nine to fifteen fathoms, in September, 1874. 



According to Dall the color of the living animal was " greenish," 

 and the animals preserved in spirits showed remains of the same color 

 as a uniform grayish green. The length of these was 11.5-12.0 mm., 

 by a breadth of 8.0 mm. and a height of 5.0 mm, ; the height of the 

 rhinophoria about 2.0, of the branchial leaves about 1.0 mm. 



The form, as well as the rhinophor-openings, were quite as usual ; 

 the club of the rhinophoria with about thirty-five leaves. The gill not 

 large, with nine to twelve leaves ; the space within the gill as usual, 

 also the arms and the renal pore. The back covered with granula- 

 tions and short clubs. The head, with the tentaculaj and the genital 

 opening as usual. 



Three individuals were dissected ; the peritoneum was colorless. 



The central nervous system showed the cerebral ganglia larger than 

 the visceral, which were lying on the outside of and behind the former, 

 very distinct from them ; the pedal ones being intermediate in size 

 between the cerebral and the visceral ganglia. On the exterior part of 

 each cerebral ganglion a little short-stalked ganglion (gang, opticum?) 

 was easily visible under a hand magnifier. The (proximal) olfac- 

 tory ganglia bulbiform, short-stalked, a little larger than the buccal 

 ganglia, which were short-oval, connected through a very short com- 

 missure ; the gastro-ojsophageal being about one-fourth to one-fifth of 

 the size of the former. In the neighborhood of the penis a little oval 

 ganglion (g. penis) having a largest diameter of about 0.25 mm. 

 (fig. 5), containing only rather small cells. 



