Liuminousness of the Sea. 315 
bag, open in the centre, and containing within it an elongated 
body, fixed, as it were, upon a pedestal, and divided at the sum- 
mit into four lobes. The mouth of the sac was set all round with 
curved tentacula, somewhat resembling tadpoles, and attached 
by their largest extremity, in number about fourteen. The 
whole of these bodies, during the time the animal was under 
the microscope, were in constant motion, the edges of the sac 
contracting suddenly, and as quickly opening again; the central 
body and the tentacula moving simultaneously. The natural 
size of this interesting little animal was about that of a small 
pin’s head. A figure of a Medisa is given by Macartney, of 
the natural size, ities has some resemblance to this animal I 
have described, but differing materially in many respects. 
This which T have copied from Macartney’s paper (fg. 82. e), 
may be compared with mine. The family resemblance is 
sufficiently great to constitute them of the same genus. In ad- 
dition to these animals, all of which may be perhaps referred 
to the Medusa and Actinia tribe, there occurred two other 
bodies of a different figure and construction, and apparently 
animals. The first of these (fg. 83.a) occurred in consider- 
CS 
ENS 
able quantity, especially in the Straits of Malacca and in the 
Java Sea; and though I cannot say I observed these bodies 
distinctly luminous, they seldom occurred except at such 
times as when the sea was vividly so. They are composed of 
a series of short, oval, hollow tubes, quite transparent, finely 
jointed to each other by a narrow neck, and so exceedingly 
brittle that it was impossible to obtain any thing but frag- 
ee 
