THE 



GARDENER'S MAGAZINE, 



SEPTEMBER, 1843. 



ORIGINAL COMMUNICATIONS. 



AuT. I. Comparative Physiology. By R. Lymburn. 



{Continued from p. 396.) 



In Book II. On Special and Comparative Physiology, Chap. V. 

 On Ingestion and Absorption ofAlimeyit in general, he says: — " The 

 peculiar characteristic of living beings has been stated to be 

 the power which each possesses of maintaining, for a certain 

 period, its form and structure, in defiance of the physical pro- 

 perties of its parts, which are at the same time undergoing 

 alterations both in composition and form. In the developement 

 of the germ, it is not so much the structure itself which is fur- 

 nished by the parent, as the capability of forming that structure, 

 by the conversion of external materials into organised tissues, 

 possessed of peculiar properties, by the process of assimilation, 

 These materials constitute the aliment necessary for the deve- 

 lopement of the living system, and in pro23ortion to the ac- 

 tivity of its operations Avill be the occasion for their supply. 

 The larvaa of the flesh fly are said to increase in weight 200 

 times in 24 hours. The Bovista gigantea, a fungus of the 

 puff'-ball tribe, has been known to increase in one night from 

 the size of a mere point to that of a huge gourd, estimated to 

 contain forty-seven thousand millions of cellules." 



From the opinions above stated, it will be perceived Dr. Car- 

 penter takes a different view of developement from that enter- 

 tained by Bonnet, Main, and others. The different opinions on 

 this subject are given at great length in the late edition of 

 Mliller's Physiology, who, as we stated before, considers the 

 power only of reproducing the individual to reside in the germ. 

 It is potentially not actually, he says, the new being. The ob- 

 servations of Schwann have shown " that in a preexisting struc- 

 tureless substance, which may be situated either within or on 

 the exterior of cells already formed, new cells are developed in 

 a manner regulated by determinate laws, and these new cells 

 SdSer.— 1843. IX. hh 



