PHILOSOPHICAL TRANSACTIOKS. 



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figure of the manner in which the flustra foliacea fastens itself to shells ; see 

 fig. 4. This figure is a little magnified, to show the form of the cells, as they 

 have spread themselves over the surface of the scollop-shell. The advocates for 

 the vegetation of zoophytes, I hope, will be convinced, that the part that sticks 

 to the shell is not a root, but only a single course or layer of cells of the same 

 animal. As it rises into leaf-like branches they become double, or 2 layers of 

 cells, placed in such an opposition to one another as to strengthen the whole, 

 like the cells in the honey-comb ; and what is very singular, the narrow part of 

 the stem near the shell, often consists of 4 or more layers of cells, which the 

 animal, by this kind of instinct, most certainly applies to strengthen that slender 

 part against tlie force of the waves. For another instance of the base of a 

 zoophyte spreading downwards to secure itself, we have an example in the 

 madrepora muricata, which is extending itself over a dead animal of the same 

 species, as in fig. 5. ; 



The following remark of Dr. Pallas will show, that as he conceives the wood 

 or horny stem to be composed of tubes, so he thinks that there is a communi- 

 cation of juices from the polypiferous pores on the cortical part, to the inside or 

 horny part, as in trees : for he observes, that as the trunk of the gorgonia is 

 always proportioned to the size of its branches, the wood or horny part of the 

 trunk, notwithstanding its hardness, must necessarily thrive, grow, and increase 

 every way, even though the organs of the bark, or surrounding fleshy substance, 

 at the trunk and base are obliterated ; and hence he concludes, that the trunk 

 must receive nourishment from the branches, and apprehends, this nourishment 

 to be absorbed and prepared by polypiferous pores. Now it is evident, that the 

 idea of the trunk and base of a tree growing in thickness, when it is divestetl of 

 its surrounding bark, is contrary to the known laws of vegetation. The only 

 method of increase in the trunks of trees is by the apposition of new layers from 

 the bark, which cannot be produced but while the bark is subsisting. 



Nor can the gorgonia increase in size, in those parts where it is deprived 

 either of the flesh with the polype suckers, or the surrounding fleshy tubes, 

 which communicate with these suckers ; for these suckers and tubes are the 

 organs that prepare and deposit the several thin layers, which form the support 

 or bony part, here called wood, as I have shown before. If, on examining the 

 internal structure of these zoophytes, it were found, that their growth and 

 fabric anywise resembled that of vegetables, this would indeed afford a pre- 

 sumptive argument, that they did participate of a vegetable nature. Yet even 

 in that case, it would be much more reasonable to suppose them animals of the 

 lowest order, raised but one degree above the vegetable tribe, than to conjecture 

 a monstrous metamorphosis repugnant to the general analogy of nature. But 

 the truth is, that though the hard parts of many gorgoniiE have very much the 



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