with descriptions of several of the objects which cause it. 433 



in the luminosity of the sea, being present in swarms. They 

 differ from the naked-eyed medusje in having the stomach ex- 

 ternal on the upper part of the umbrella. They arc brilliant 

 fellows, and flap and snap their cilia about, and at times throw 

 them up as at hg. 1 a ; this position appears to be a state of rest. 

 Fig. 1 b. shows the stomach highly magnified ; fig. 1 c, ditto 

 with the lips turned down ; 1 d, the arrangement of the tentacula ; 

 3 a, the stomach of fig. 3 : this sort is not so common, and has 

 the stomach also on the vipper side of the umbrella ; I fancy they 

 may be the gemmae of Corallines. 



I now pass to fig. 4, another of the class Diphydice, but of a 

 different shape ; these occurred several times ; the outer part is 

 glass-like, shaped like a wine-glass without a foot, the internal 

 part granular aud yellow, the widest part surrounded by pointed 

 delicate cilia, by which it moved in the most rapid manner, 

 darting about, across and up and down ; at times it would rest 

 on the sharp point, and turn round like a boy^s top when it 

 makes the last gyrations before falling, the upper part describing 

 wide circles ; this it would continue for some time, then fall down, 

 withdraw its cilia and lie on its side as if to rest ; all at once it 

 would rise and dart off on its gambols again. It very much 

 resembles the Cubiodes vitreus, fig. 3892, page 421, of Knight^s 

 ' Museum of Animated Nature,^ also figured in the ' Penny 

 Cyclopaedia,' found in the Straits of Gibraltar, where it appears 

 to have a case and live in groups. These had no case and 

 were solitary; in every other respect they were like the one 

 from Gibraltar. Fig. 5 is a much smaller specimen ; it is 

 wholly granular, still yellow, and the mouth surrounded with 

 cilia, moves quickly, generally with the cilia downwards; it 

 greatly resembled the seed of the sweet scabious, and pro- 

 bably may be the young of the other. Minute as it was, the 

 "interjections," though represented so large at fig. 6, were para- 

 sitical upon the former ; these put down their disk-like foot, then 

 turned over their rounded head, and threw a summerset, recovered 

 themselves and repeated it again and again ; and upon these para- 

 sites I observed their parasites, fig. 7y minute indeed, and which 

 I believe were Cypris in various stages of growth. 



Fig. 8 is a strange thing, evidently one in a state of trans- 

 ition, lies on its side, and runs round by jerks like the seconds 

 hand of a clock when the pendulum is taken off. When tired, 

 it closes up and assumes the form of fig. 8 a. The head part is 

 dark and granular, the wing-like appendages glassy and brilliant. 



Fig. 9, no doubt one of the same kind, found a few days after, 

 further advanced. 



Fig. 10, the tadpole of one of the Botrylli, probably Cynthia ; 

 it was beautiful, and appeared to be moored by a very delicate 



A?m. ^ Mag. N. Hist. Ser. 2. Vol. vi. 29 



