No. XI. 



HYDROZOA. 



291 



discophorous rather than to the hydroid medusae, while the 

 folds, with their thickened, convoluted, and gland-like margin, 

 which run longitudinally along the inner surface of the 



Fig. 2. Equatorial projection, magnified. This view is from below through the 

 widely open mouth, and shows the convoluted edges of the eight longitudinal 

 gastric folds. 



Fig. 3. Natural size. 



manubrium, constitute a very exceptional and striking cha- 

 racter. 



The marginal lobes of the umbrella are in the form of 

 short truncated cones, each carrying several papilliform and 



TT 2 



