>•'"''"■„„■, 



SCYPHOMEDUSAE COLLECTED BY STEAMER ALBATROSS." 205 



ature, and thus it is barely able to survive in the surface waters of 

 the warmer seas in summer. Romanes found that specimens of this 

 medusa from the British seas can withstand being frozen solidly 

 into ice, and I find this to be true also of this medusa from Halifax, 

 Nova Scotia. At Halifax, on the other hand, the medusa ceases to 

 pulsate at 29.4° C.,at which temperature it is most active atTortugas, 

 Florida. On the other hand, the Florida medusa is killed by being 

 frozen into the ice. Thus the medusa becomes somewhat acclimated 

 to the temperature of the waters in which it lives, and if accustomed 

 to warm water it loses its resistance to cold and the opposite. 



AURELLIA LABIATA Chamisso and Eysenhardt. 



Aurelia labiata Chamisso and Eysenhardt, 1820, Nova Acta Phys. med. 



Leop. Car., vol. 10, p. 358, pi. 28, figs. 1 A. B. 

 Aurellia labiata Mayek, 1910, Medusae of the World, vol. 3, p. 628, fig. 398. — 



Light, 1914, Philippine Journal of Science, vol. 9, p. 200. 



Light (1914) rec- 

 ords a specimen from 

 the Philippines, the 

 bell of which was 225 

 mm. in diameter. 



Aurellia labiata dif- 

 fers from A . aurita by 

 having 16 notches in 

 its bell-margin, by its 

 peculiar velum - like, 

 interrhopalar, subum- 

 brella membranes rep- 

 resenting the true bell- 

 margin, and by the 

 very small size of its 

 subgenitalostia. The 

 mouth-arms are also 

 shorter than one com- 

 monly observes them 

 to be in J., aurita, and 

 the terminal branches 

 of the radial-canals, 

 anastomose to a 

 greater degree than in 

 A. aurita. 



The dimensions of three specimens, Cat. No. 27923, U.S.N.M., ob- 

 tained by the United States Fisheries Bureau steamer Albatross at 



Fig. 11. — Aurellia labiata fkom the Philippines. A, 

 Oral view showing the 16 notches in the bell 

 magrin. b, aboral view of tentacles and lappets. 

 C, Diagrammatic cross section of bell margin. 

 c, eing canal ; ex, exumbrella ; I, lappets ; re, racial 

 canal ; sw, subombp.ella ; t, tentacle ; v, velarium. 



