114 EIGHTH REPORT 1838. 



the animal, whilst others more delicate terminated in a mesentery, sup- 

 porting the gemmiferous bodies, or what has been erroneously called 

 the ovary. The division of the stomach into two lateral parts, giving 

 to the wliole animal a bilateral symmetry, Avas pointed out. 



The Gemmiferous bodies are about 200 in number, and appear as 

 elongated masses attached along the inner border of most of the leaf- 

 lets. Each is composed of several horizontal folds or plaits, which, 

 when carefully unfolded, may, by the assistance of a lens, be seen to 

 consist of two delicate layers of membrane, enveloping one closely 

 compacted layer of gemmules. After enveloping the gemmules, the 

 membranous layers become placed in opposition, and form the mesen- 

 tery, by which the gemmiferous body is attached to the leaflet. The 

 gemmules are round, except in an advanced stage of development, 

 when their outline becomes interrupted by the pressure of neighbour- 

 ing gemmules. A well-marked central depression may also be seen 

 indicating the situation of the oral aperture, but without tentacula; 

 when of large size, they form considerable depressions in the gem- 

 miform bodies, protruding before them their delicate investing mem- 

 brane. In this state, they are readily detached by the point of a 

 needle. Their size is nearly uniform, except a few small ones, scat- 

 tered very generallj" amongst the whole. There is no gradation in size 

 amongst them, as if they successively arrived at maturity, as imagined 

 by Dr. Spix. Some of the gemmules are, however, less developed than 

 others ; and at the same season of the yeai-, it is not uncommon to find 

 individuals with the gemmules in very different stages of development, 

 and this is not limited to any particular season. The colour of the 

 gemmules varies considerably. The Vermiform Filaments. — They are 

 attached by a delicate mesentery to the internal border of each gem- 

 miferous body ; they are formed of numei'ous convolutions extending 

 from the superior to the inferior part of the gemmiferous body. They 

 are of a milk-white colom-, about as thick as a horse-hair, extremely 

 soft, yielding readily to pressure with a needle. Superiorly, the fila- 

 ments are very minute, so that their oi'igin cannot be detected. In- 

 feriorly, they are of larger size and less convoluted, passing in a simple 

 wavy line to the stomach, where they terminate. During life, these 

 filaments exhibit a distinct vermicular motion, even after removal from 

 the animal. On removing some from the animal, and placing them in 

 sea-water, they exhibited considerable locomotive power, which lasted 

 for some time, when their outline became obscured, and in twenty-four 

 hours nothing remained but a whitish flocculent substance. This struc- 

 ture is best seen in its living state. In fresh water it decomposes in 

 half an hour, but in proof spirit less rapidly. The author has succeeded 

 in preserving it best by spreading the filament and its mesenterj' 

 upon glass, upon which they may be dried. The function of these 

 filaments is involved in obscurity. By many, they have been regarded 

 as oviducts, but this the author thinks is very improbable, both from 

 the minuteness of their terminations, the size of the gemmules, and the 

 fact of ova never having been detected in them. In fact, the repi'o- 

 duction of Actiniae must be looked upon as a strictly internal gemmi- 



