124 CLASS III. 



This family nearly coincides with the genus Gyancea Cuv. The 

 four openings beneath the disc, conducting to the cavities which 

 contain the organs for propagation, were by PERON and LAMARCK 

 incorrectly considered to be four mouths. 



Cyancea Cuv. (and species of the genus Pelagia ejusd.) 



Genera : Sthenonia ESCHSCH., PhaceUophora BR., Cyancea 

 ESCHSCH., Aurelia PERON; Pelagia PERON, Chrysaora PERON, 

 Ephyra ESCHSCH. (Euryale and Ephyra PERON.) 



Sp. Cyancea aurita, Medusa aurita L. ; MUELLER Zoolog. danic. Tab. 76, 77 ; 

 EHRENB. Abhandl. der Alcad. zu Berlin, physik. Klasse 1835 ; Cuv. R. 

 Anim. edit, ill., Zooph. The four arms are considerably longer in old than 

 in younger specimens ; these arms consist of two laminae crumpled at the 

 edges, which during life face each other in such a way as to form a canal ; 

 after death they are flaccid and parted asunder. The disc is not quite 

 circular, but in some degree divided by indentations of the margin into 

 eight lobes. The four arms unite at the center of the body to form a 

 circular aperture : this mouth leads to the stomach, which has four lateral 

 cavities. From the stomach there run sixteen vessels to the margin of the 

 disc, of which eight, divided into branches, alternate with eight others un- 

 divided and open at the margin. In addition, there are eight corpuscles at 

 the margin, which EHRENBERG considers to be eyes, and which were noticed 

 above. This species is found in the North Sea and the Baltic. Comp. 

 H. M. GAEDE Beitrdge zur Anatomie und Physiologic der Medusen, mit 

 i Kupfertafeln, Berlin, 1816, 8vo ; BAER Ueber Medusa aurita, MECKEL'S 

 Archiv fur die Physiol. vm. 1823, s. 369391, with fig. ; F. KOSENTHAL 

 Beitrag zur Anatomie der Quallen, Zeitschrift fur Physiol., herausgegeben 

 von F. TIEDEMANN, G. R. und L. C. TREVIRANUS, I. 2, 1825, s. 318 330, 

 with fig. 



Gyancea capillata, Medusa capillata, BASTER Natuurk. Uitsp. n., Tab. v. 

 fig. i. 



Pelagia noctiluca ESCHSCH., Medusa noctiluca FORSK., WAGNER Bau der 

 Pelag. noctiluca and Icon. Zool. Tab. XXXIII. ; in the Mediterranean, &c. 



Ephyra ESCHSCH., probably rests on young forms of Cyancea; comp. 

 WILL Hor. Tergesl. Tab. n. fig. 20, and SARS in ERICHSON'S Archiv, 1841, 

 Tab. n. 



Family IX. Oceanidce. Disc without lateral cavities to in- 

 close generative organs. Body campanulate. Mouth and oeso- 

 phagus often elongated into a proboscis. Arms conspicuous or 

 lobes around the mouth. Canals proceeding from the stomach 

 elongate. 



