MedusoB and Ctenophora 11h 



Station 41s, Bernard harbour, Dolphin and Union strait, Northwest terri- 

 tories, August 24, 1915. 



Station 40d (crack in ice). Dolphin and Union strait, Northwest territories, 

 June 8, 1915. 



Station 293», 50-150 fathoms, crack in ice, lat. 70° 20' N., long. 140° 30' W., 

 April 6, 1914. One very fragmentary. 



Station 29sf2, 0-150 fathoms, crack in ice, lat. 70° 20' N., long. 140° 30' W., 

 April 6, 1914. One very fragmentary. 



Station 57a, cape Smyth, point Barrow, Alaska, August 8, 1916. One very 

 fragmentary. 



In all there are perhaps thirty specimens. But for the most part they are 

 mere shells, minus margin, gonads or manubrium; identified as Aglantha chiefly 

 on the strength of their rather characteristic outline. In height, such of the^ 

 specimens as can be approximately measured range from about 5 to about 15 

 mm. 



Such poor material could not be expected to add anything to our know- 

 ledge of a species as well known anatomically as is Aglantha digitale, while, 

 owing to the total destruction of the marginal organs in all the specimens, they 

 throw no light on varietal differences which have been the subject of much 

 discussion in this genus. In no case is an otocyst intact. 



The records, however, are of interest, geographically, as bridging a gap in 

 the known distribution of Aglantha, the genus being previously known from 

 Labrador to the east, Bering sea and off point Barrow (Fewkes, 1885) to the 

 west of the region in question. 



NaECOMEDUSjE. 



Family AEGINID^ Gegenbaur. 



Aeginopsis laurentii Brandt. 



Plate II, Fig. 3. 



Aeginopsis laurentii Brandt, 1838, p. 363, pi. 6, fig. 1-6. For synonymy, see Mayer, 1910, 

 p. 472, 498. 



Station 27g, 1 fathom, September 26, 1913, off CoUinson point, Alaska; 

 ice, 8 inches; 2 specimens. 



Station 27r, 1 fathom, October, 2, 1913, off Collinson point, Alaska; 30° F. 

 temperature; ice, 10 inches; 1 specimen. 



Station 30a; 3 fathoms; May 4, 1914; 69° 41' N., 141° 11' W. Hole made 

 in ice 6 feet thick; 1 specimen. 



Station 27m, September 19, 1913, off Collinson point, Alaska; ice, 8 inches; 

 3 specimens. 



Station 21 n, September 20, 1913, off Collinson point, Alaska; 30° F.; ice, 

 8 inches; 2 specimens. 



The specimens range from 3 to 12 mm. in diameter. 



This characteristically arctic, and easily recognized Narcomedusa has been 

 fully described within recent years by Maas (1916), by Hartlaub (1909), and 

 by me (1909''). Indeed, since the first account of it„ by Brandt (1838), there 

 has been no doubt of its identity. Its most diagnostic features are the presence 

 of only four tentacles, but 8 peronii, and the total absence of a peripheral canal 

 system, contrasted with the presence of 8 bifid, i.e., 16, gastric pouches, the 

 wrinkled oral surfaces of which bear the genital products, particularly next 

 their outer margins, ■^hich are more or less lobed'. There are no otoporpae, but 

 the otocysts are of the usual Aeginid type, 3 or 4 per octant in the largest speci- 

 mens, as I have already pointed out (19096, p. 315). All these features are 



