390 Messrs. M ^Andrew & Forbes on new or rare British Animals. 



XL III. — Notices of new or rare British Animals observed during 

 C7'uises in 1845 and 1846. By Robert M^Andrew, Esq., 

 and Professor Edward Forbes. 



[Continued from p. 98.] 

 [With a Plate.] 



II. On the occurrence of a species o/Pelagia in the British seas. 



On the 23rd of August 1846, when cruising off Mount^s Bay, 

 Cornwall, our attention was attracted by some rather large Me- 

 dusae which passed the vessel at intervals. The weather was fine 

 and the sea smooth ; the Medusa? in question appeared like 

 rose-coloured globes in the water. On capturing some we found 

 they belonged to a species of the genus Pelagia, hitherto un- 

 noticed in the British seas. 



The following description was drawn up from the living ani- 

 mal (which is figured in Plate IX. fig. 5) : — 



Disc 2^ inches in diameter; subglobose, slightly depressed 

 above, hyaline and tinged with pink, covered with small reddish 

 orange warts which become obsolete towards the summit ; mar- 

 gin with sixteen lobes, each bilobed : each lobule rounded and 

 having a triangularly-lanceolate centre covered with reddish 

 brown warts, which are also seen on the sides of the lobules, but 

 are there not coloured. From beneath the separations of eight of 

 the greater lobes spring as many tentacula : in the notches of 

 the remaining eight are the ocelli. Ocelli composed each of an 

 ovate red body (formed of pigment cells and prismatic crystals) 

 suspended by a peduncle from a translucent (ganglionic ?) mass, 

 whence radiate fibres (nerves ?), and behind which (connected by 

 a nerve ?) is a circular cavity containing an otolitic body in con- 

 tinual revolution. 



Tentacula pink, simple, hollow, short when contracted and 

 nearly equal throughout, but capable of extreme extension (even 

 to the length of several feet) ; they consist of an external epi- 

 dermic sex'ies of large pigment cells, forming a sheath or tube 

 which is strengthened within by eight longitudinal ribs or co- 

 lumns of compact contractile granular tissue. 



Beneath, the subumbrella presents four dependent arms united 

 at their bases, but separated again so as to form a central cavity 

 with four openings. In the central cavity we find four purple 

 furbelowed reniform ovaries (containing irregularly lobed germs), 

 separated by four masses of contractile tubes (spermathecal ?) 

 full of minute swarming bodies (spermatozoa ?) : the ovaries are 

 fringed by similar tubes. From the gastric cavities run sixteen 

 or more vessels to the margin, obscurely branching. 



