451 



nate Histo-plasts, or Histo-plastic Germs, and I conceive 

 them to be of three kinds, Granules, Fibres, and Cells. The 

 accompanying Table will exhibit more clearly my views of the 

 order of precedence of the elementary parts of the organic 

 fabric : 



AMORPHOUS ORGANIC FLUID. 



From which become developed — 

 I. 



A-PLASTIC ELEMENTS. 



1 . Primary Organic Granules : 



(a) Isolated ; 



(b) Aggregated ; and thus forming — 



2. Granular Corpuscles ; or, 



3. Granular Stroma or Base. 



4. Hyaline Membrane (Cell Membrane, &c.) 



5. Hyaline Stroma or Base. 



6. Hyaline Vesicles. 



II. 



HISTO-PLASTS OR TRUE HISTO-PLASTIC GERMS. 



7. Plastic Corpuscles,' Granules, Nucleoli, Nuclei, and other 



Germs, if any. 

 8r Fibres (themselves formative elements). 

 9. Cells. 

 10. Definite Tissues. 



It is unnecessary here to go farther into the study of 

 these individual elements, the forms of which must be familiar 

 to all experienced microscopic observers ; to the class of hyaline 

 structures evidently belongs the membrane alluded to by 

 Schwann, and whose formation even he found it difficult to re- 

 concile with the exclusive adoption of his cell theory. He ob- 

 serves in reference to it : "In many glands, as for instance the 

 kidneys of a young mammalian foetus, the stratum of cells sur- 

 rounding the cavity of the duct is enclosed by an exceedingly 



