80 Natural History of British Zoophytes. 



veloped into polypes in the lateral denticles and extreme cells. Such 

 was the deduction he came to from observations made on the growth 

 more especially of the Sertularia abietina, which he had kept alive 

 for nearly four months in a vessel of sea water. When a new part 

 was formed, there first emerged from the stem a minute tubular 

 joint, which rose to four, five, or even eight lines in height : after 

 some days some lesser buds, regularly disposed in an alternate man- 

 ner, were seen on the sides of this branch, which in the course of 

 four or six days grew into cells containing perfect polypes. Hence 

 it is obvious to Baster that the stem of this and similar zoophytes 

 grows in thickness and length as plants do, and that the medullary 

 pith is animal, which it is not wonderful should assume a dendroi- 

 dal form, when we see zinc and quicksilver do the same by the mere 

 force of affinity. Trembley had already pronounced the cells of the 

 fresh-water zoophytes (Plumatella) to be not the work of the po- 

 lypes, but rather compartments in which they concealed a part of 

 their body ; and this fact, added to those already given, makes it 

 certain that the animalcules of- the Sertulariadee are entirely pas- 

 sive, and have no more to do with their polypidoms than the flower 

 has with the increase and growth of the herb. * 



There is some ambiguity in Baster's statement of his opinions, 

 for it is not very obvious whether he believed the new formed branch- 

 lets to be themselves the eggs or seeds, or whether they only con- 

 tained the eggs ; but be this as it may, it appears scarcely doubtful 

 that he knew nothing of the true ova and their curious ovaries. 

 The phenomena observed in the production of new parts are cor- 

 rectly stated, but nothing but wilful prejudice could blind him to 

 the fallacy of the consequent reasoning. The analogy attempted to 

 be drawn between the eggs of zoophytes and the seeds of plants 

 has no existence, for every tyro knows well that the coat or skin of 

 seed in no instance ever pushes forth radicle fibres, or ever exhi- 

 bits any sign of vegetation ; — it is a dead part which is cast off or 

 corrupts, and exerts no further influence on vegetation than as a 

 protection to the cotyledons and embryo which it invests, so that if 

 it is true that the coat of the ova of zoophytes is the source of their 

 vegetative part, as Baster says, that coat must be of a very differ- 

 ent nature from the skin of seeds. It would have been better to 

 have compared the oviform bodies of the zoophyte with the buds of 

 the tree, and he might have disported with this fancy to some ef- 

 fect, for there are many analogical resemblances, and the inapplica- 



* Phil. Trans, vol. lii. p. 108-118 — For Baster's works see Hall. Bib. Bot. 



i. 468. 



3 



