CELLULAR SUBSTANCE. 323 



in their interstices. This tissue is not sufficiently abundant in 

 the bones, tendons, or cartilages, to be very distinct; but from 

 what is seen of it in the forming stage of the embryo, it is ne- 

 vertheless ascertained to be the base of every part. In glan- 

 dular textures it is frequently spoken of under the name of pa- 

 renchyma, 



Most of the membranous textures of the body may by ma- 

 ceration be resolved into this mucous or cellular tissue, so that 

 we hear anatomists, without hesitation, asserting, that under 

 various degrees of consistence, it forms the skin, the serous 

 membranes, the vessels, the ligaments, in short, almost every 

 thing excepting the bones, the muscles, the nervous system, 

 and the glands, and they only depart from it in having their 

 globules deposited in its interstices.* Meckel even adds to the 

 list the epidermis. 



The term mucous tissue was substituted for that of cellular, 

 by Bordeu,t owing to its glue-like consistence, and to its re- 

 semblance to the corpus mucosum of vegetables. Notwith- 

 standing its propriety on these grounds, yet as the lining mem- 

 brane of all the hollow viscera has the same name, some con- 

 fusion may be produced unless one bears in mind the distinc- 

 tion. Bordeu has expressed the character of the internal 

 cellular membrane very forcibly in saying, that in embryos all 

 their organs are species of buds, which vegetate in the cellular 

 tissue, like plants do in the open air, or their roots in the ground, 

 and that each one having an apartment of its own, this apart- 

 ment is to it a cellular atmosphere, which keeps in a perfect 

 relation with the action of the organ.J 



In tracing many of the laminae of the cellular substance, we 

 find, that as life advances, they assume a more fibrous charac- 

 ter than what they possessed in infancy; this also occurs when 



* Beclard, Anat. Gen. p. 141. Haller, loc. cit. p. 19; vol. i. p. 113. 



t Loc. cit. 



t Loc. cit. p. 65. Rechcrches Anatomiques sur les Glands, Paris, 1752. Also-, 

 An Exposition of the Physiol. and Pathol. Doctrines of Theoph. Bordeu, under-, 

 stood to be from the pen of a learned friend, R. La Roche, M. D., in the North 

 American Med. and Surg. Journal. Philad. April, 1826. 



