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VOL. LXVl.J PHILOSOPHICAL TllANS ACTIONS. 72 1 



the red coral should be added. This you thought the more necessary, as the 

 accounts already published of them by Dr. Linnaeus and Dr. Pallas seemed to 

 make them of a mixed nature in their growth, between animals and vegetables : 

 a thing not easily to be reconciled to the usual operations of nature. I was so 

 fortunate about that time to receive a most excellent collection of different spe- 

 cies of these animals, preserved at the sea side in spirits, at Dominica, which 

 has enabled me to show more clearly, that they are true animals, growing up in 

 a branched form, and in lio part vegetable. 



From the following observations it will appear, that the gorgonia is an animal 

 of the polype kind, resembling the common fresh water polype in many of its 

 qualities, but differing from it in the remarkable circumstance, of producing 

 from its own substance a hard and solid support, serving many of the purposes of 

 the bone in other animals. Every one knows, that the common polype sends 

 out its young from its side, like buds, which being grown to the form of the 

 parent animal, to which they still adhere, send out again their own young, like 

 buds, adhering to themselves ; and this is repeated, till at length the whole ac- 

 quires a branched appearance, resembling a vegetable ; see fig. 1, pi. 15. The 

 gorgonia grows nearly in the same manner ; and hence arises its resemblance to 

 a shrub, which has given occasion to the mistake of placing it in the vegetable 

 kingdom. But though the nature of these animals is so much like the polypes, 

 they differ in several circumstances ; the most remarkable is that already men- 

 tioned, the hard bone by which the gorgonia is supported. This is not formed 

 by any kind of vegetation, but by a concreting juice thrown out from a peculiar 

 set of longitudinal parallel tubes, running along the internal surface of the 

 fleshy part. In the coats of these tubes are a number of small orifices, through 

 which the osseous liquor (if I may use the expression) exudes ; and concreting, 

 forms the layers of that hard part of the annular circles, which some, judging 

 from the consistence rather than the texture, have erroneously denominated 



wood. h'rvif:'!- 



Dr. Pallas, in his Elench. Zoophytorum, p. 162, is of opinion, that the 

 layers of which the wood, as he calls it, of the tougher gorgonias is composed, 

 may be separated into numerous longitudinal fibres ; that the longitudinal striae, 

 which frequently appear on its external surface, are owing to this structure ; and 

 that these fibres are in fact hollow, like the wood of trees, the cavity of the 

 tubes being closed up, as they become hard and rigid. 



I was nearly of the same opinion when I was writing my Essay on Corallines, 

 as may be seen in the Philos. Trans, vol. 48, p. 1 8, and also p. 504, where I 

 have compared the herring-bone coralline, which is composed of many little 

 tubes, to the growth of sea-fans and sea-feathers, now called gorgoniae ; and 

 likewise in my Observations on the Growth of the red and white Coral, see 



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