402 APPENDIX. NOTES. 



infused, it would be nothing extraordinary either that they 

 should be mistaken for moving molecules, or moving mole- 

 cules for them. Farther we may observe a kind of analogy 

 between the spherical Infusories and the Molecules, and 

 between the filiform ones transversely annulated with a 

 vermicular motion, and the fibrils of Mr. Brown. 



Another law of nature seems to result from the experi- 

 ments of this acute naturalist that all bodies whether 

 organized or inorganized, are formed, as fibrin is in the 

 animal kingdom, by spherical molecules made, as it were, 

 into necklaces, and then adhering in bundles, and that 

 these are the substratum of all substance. In fluids the 

 spherules are not united, and so have free motion inter se. 



NOTE 22, p. 1 98.- Several of them, for it is not common 

 to them ally when touched cause a sensation similar to that 

 produced by the sting of a nettle. Aristotle mentions a 

 marine animal, under the name of Acalephe, 1 and another, 

 if it be not the same, under that of Cnide,* both of which 

 words, according to the Greek lexicographers, are used to 

 designate the same plant, the stinging-nettle; 3 but it 

 seems not quite certain that, in either case, he had the 

 stinging Gelatines or sea-nettles in his eye. Describing 

 his Acalephe, he says, " It adheres to the rocks, as do 

 some of the shell-fish, but sometimes it roves at large. 

 It has no shell, but the whole body is fleshy. If the hand 

 is moved to it, it perceives, seizes, and adheres to it, like 

 the Polype, by means of its tentacles, 4 so that the flesh 

 swells. It has its mouth in the middle, and the rock 



1 Gr. A/caXr/07;, Aulus Gellius (Noct. Att. 1. iv. c. 11.) writes 

 it AKaXvfyrj. 



2 Gr. KviSr). 3 Heschius explains AfcaX>;0at by 

 4 Gr. 7r\Kravai. 



