BEROE. ACALEPHA. 415 



Gen. 15. BEIIOE, Mull. 



Body oval or globular, with projecting ciliated ribs, in which 

 are vascular ramifications ; mouth at one extremity, conduct- 

 ing into a stomach which occupies the axis of the body. 



B. ovatus, Fleming. Body orbicular, slightly depressed at the sum- 

 mit, and a little protuberant at the base, with eight denticulated 

 vertical bands or ribs. Brit. Animals, 502. 



The genus Callianira of Peron differs not from the preceding but in the ribs be- 

 ing more projecting, and joining two and two or three and three to form two kind 

 of wings. 



Gen. 16. CESTUM, Lesueur. 



Body free, gelatinous, transparent, much elongated, horizontal, 

 flattened on the sides, with one of the margins furnished with 

 a double row of ciliae ; mouth in the centre of this border 

 opening into a transverse stomach without anus. 



C. Veneris, Lesueur. About five feet long, and one inch high. In- 

 habits Mediterranean sea. Lam. ii. 465. 



This singular animal is in the form of a long gelatinous ribbon, of a milk white 

 colour, with violet reflections. 



Gen. 17. DIPHYES, Cuv. 



Body firm, but gelatinous and transparent, in the form of an an- 

 gular pyramid, with two openings at the base, one of which 

 surrounded by five points is the mouth, the other larger, sup- 

 posed to be the ovary. One species only has been observed 

 in the Atlantic ocean. 



Gen. 18. PORPITA, Lam. Medusa, Lin. 



Body free, orbicular, depressed, gelatinous exteriorly, cartilagi- 

 nous anteriorly, either naked or with tentacula at the circum- 

 ference ; upper surface flat, subtubercular, and the inferior 

 surface with striae or rays ; mouth inferior and central. 



' P. nuda, Lam. Body orbicular, flat, sub-naked. Inhabits Indian 

 ocean. Lam. ii. 484. 



These animals float on the surface of the sea, and M. Bosc, who has observed them 

 in this state, states them as resembling a piece of money supported on the water. 



Gen. 19. VELELLA, Lam. Medusa, Lin. 

 Body free, gelatinous exteriorly, cartilaginous in the interior, el- 

 liptical, flattened below, with an elevated crest on the back 

 inserted obliquely ; mouth inferior, central, projecting, and 

 surrounded with immoveable tentacula, of which the exterior 

 are largest. 



V. limbosa, Lam. Body oval, obliquely crested ; inferior surface 

 covered with white suckers, and bordered with long blue tenta- 

 cula, the mouth forming a subtubular projection in the centre. 

 Inhabits the Mediterranean sea. Lam. ii. 482. 



