554 



THE MICROSCOPE. 



arrangement of the chyliferous tubes, with their corpuscles, 

 enclosed in a structureless membrane. 



Classification of the Animal Tissues. Professor Schwann 

 classifies the fundamental tissues of the human body as 

 follows : and it will be seen that more than half are made 

 up of cellular tissue or simple membrane. 



1. Simple membrane : employed alone 



in the formation of compound 

 membranes ........ 



2. Fibrous tissues 



(Examples : Walls of cells, capsule of 

 < lens of the eye, sarcolemma of mus- 

 { cle, &c. 



(Examples : White and yellow fibrous 

 tissue, areolar tissue, elastic tissue, 

 &c. 



= Cellar tissues 



4. Sclerous or hard tissues .... 



5. Compound membranes : composed 



of simple membrane and a layer 

 of cells of various forms (epithe- 

 lium or epidermis), or of areolar 

 tissue and epithelium .... 



6. Compound tissues ; a, those com- 



posed of tubes of homogenous 

 membrane, containing a peculiar 



(Examples: Rudimentary skeleton of 

 \ invertebrata, bone, teeth, &c. 



Examples : Mucous membrane, skin, 

 true or secreting glands, serous and 

 synovial membranes. 



Examples: Muscle, nerve. 



'o" 111 : 6 brou : } iw 



Cellular Membrane or Tissue. Cellular or areolar tissue 

 is generally distributed throughout the body, and various 



forms of this cell fibre are 

 , found ; it is seen uniting to- 

 )4= gether component parts, filling 

 ""'; up interstices between them, 

 * and affording a support to the 

 : blood-vessels and nerves, be- 

 ' fore they are distributed to the 

 1 various organs. This fibre is 

 I soft, clear, smooth, and ex- 

 tremely minute, being the 

 1-1 2,000th of an inch in dia- 

 meter, sometimes less. The 

 fibre is usually found united 

 together in bundles, the 

 l-2000th of an inch broad : if 



Ing. 291. Fibrous tissue, lining the in- , - , 1 -j.-i , 



lerior of 1he eggshell, the lime hav- these be acted Upon by dilute 

 ing been previously removed by im- oppf^ <\r*\f\ tVlPV RW^ll UD 

 mersion in dilute hydrochloric acid. acetlc acm > tne 7 tii * "P> 



become transparent, and the 



appearance of fibrous structure is no longer seen, although 

 some fibres that were not previously observed may become 



