14n Canadian Arctic Expedition, 1913-18 



Both of the larger (but still immature) specimens have lost most of their 

 mouth parts and tentacles, and are otherwise in poor condition. They are 

 recorded as belonging to the var. capillata of this widespread and well-known 

 species, because of their close resemblance to the specimens of C. capillata var. 

 capillata, which I have previously described from Bering sea (1913, p. 92). 

 Particularly important, as locating them in this section of the species, are the 

 facts that the sixteen muscular trapezia of the subumbrella are practically 

 continuous, one with another, hardly separated at all; and that the clefts 

 limiting the rhopalar lappets are shallow and the interradial marginal clefts 

 broad (1913, pi. 4, fig. 8). The arrangement of the lappet canals is likewise 

 the same as in the Bering sea examples. But they are not in good enough 

 condition to throw any light on the varietal relationships in this variable genus. 

 Whatever colour they may have exhibited in life has now disappeared. 



Family AURELIID^B L. Agassiz. 

 Aurelia limbata Brandt. 



Aurelia limbata Brandt, 1834, p. 26, Vanhoffen, 1902, p. 43; Maas, 1906, p. 507; Bigelow 

 1913, p. 99, pi. 5, figs. 1-4. Diplocraspedon limbata Brandt, 1838, p. 372, pi. 10. 



Station 20/, Grantley harbour, port Clarence, Alaska, August 3, 1913; 

 surface; 3 specimens about 75, 50, and 36 mm. in diameter. Also, many noted 

 as " seen in the water." 



These three specimens, the largest of which bears well-developed gonads, 

 are crumpled and partly decomposed. But the canal system is sufficiently 

 preserved to show that they are the same form as the specimens from the Aleutian 

 islands and northern Japan, which I have referred to the A. limbata of Brandt 

 (1913, p. 99). As I have pointed out, this species (if indeed it deserves so dig- 

 nified a rank) is separable from the more widely occurring A. aurita chiefly by 

 the very complex anastomosis of its canals. And though this character is 

 a trivial one and not sharply defined, thanks to it A. limbata is decidedly 

 different from A. aurita in general appearance. In the present specimens, as in 

 the much better ones which I have already described from the Kurile islands, 

 from the sea of Okhotsk, and from northern Japan (1913, p. 99), the perradial 

 and interradial groups of canals divide, subdivide, and anastomose so com- 

 plexly that the entire subumbrella surface is occupied by a close-meshed canal 

 net. And even the adradial canals, which are straight and unbranched over 

 their inner halves, take part in the general anastomosis for the outer half of 

 their length. 



A second character which has been used to separate limbata from aurita is 

 the marginal pigmentation of the former; and this was a striking feature of the 

 Bering sea series collected by the Albatross (1913, p. 100). In the present case 

 this pigmentation, if once present, has been lost probably the result of very 

 poor preservation. But the Aurelia seen off cape Smyth, point Barrow, Alaska, 

 station 57a, August 8, 1916 (none preserved) are described by Mr. Johansen as 

 having the tentacles yellow brown (these, however, may not have been limbata) . 

 Because of their poor condition the specimens add nothing to previous accounts 

 of the anatomy of the species. Their principal interest is geographic. 



This same variety, or species, of Aurelia, whichever it finally proves to be, 

 was apparently taken by the Tjalfe expedition in Greenland waters (Kramp, 

 1913, p. 281), for Kramp's series show the same complex anastomis of the canals 

 as is characteristic of Aleutian and Bering Strait specimens. Kramp, it is true, 

 believes that they cannot be referred to limbata, because differing from it in 

 the degree of pigmentation and outline of the bell. But the structure of the 

 canals is so much more important than either of these characters that they are 



