TISSUE. [ : 



BiBL. Ehr. Inf. 294 ; id. Ber. Berl Ak. 

 1840 ; Duj. Inf. "561 ; Ann. JV. K. 1879, iv. 

 290; Clap, et Lacli. Inf. 195; Kent, Inf. G03. 



TISSUE, FiBEO-PLASTic. — A term ap- 

 plied by Lebert to imperfectly developed 

 abnormal connective tissue. The separate 

 elements are often found diffused through 

 normal tissues, or products of inflammatory 

 exudation. They consist of rounded or 

 oblong cells, froiu 1-2300 to I-KjOO" in dia- 

 meter, in a more advanced stage becoming 

 fusifonii or angular, and finally forming di- 

 stinct hbres ; hence resembling the elements 

 of embryonic connective tissue (PI. 49. fig. 

 42). In some instances the development is 

 arrested at one of the early phases, so that 

 the tissue consists almost exclusively of the 

 rounded or the fusiform cells; and in others, 

 the cells enlarge and produce a number of 

 nuclei or secondary cells (PL 38. lig. 10 c). 



Eibro-plastic tissue or its elements are 

 met with in inflammatory efl'usions upon the 

 serous and synovial membranes (but rarely), 

 in the interstitial effiisions of pneumonia, 

 especially when chronic, in cirrhosis of the 

 liver, in the products of suppurating sur- 

 faces, on the surface of chronic ulcers and 

 non-malignant fungoid vegetations, in the 

 soft yellow vascular tissue occupying the 

 cancelli of ulcerated bones, in certain tu- 

 mours, &c. 



BiBL. Lebert, Thys. Path. ; Wedl, Path. 

 Hist. ; Fbrster, Path. Anat. i. ; Riudfleisch, 

 Path. Geioebcl. 



TISSUES, Animal.— The following syn- 

 optical arrangement of the principal animal 

 tissues, according to their structure, is in- 

 tended to facilitate reference to the various 

 articles scattered through the work. 



A Simple. 



1. Blaslemic or protoplastic . Barcode. 



2. Memt)ranoii.s Basement membrane. 



(Fatty tissue ; epithelium ; 

 nerve-cella ; simple 

 cartilage ; unstriated 

 muscular fibre. 

 (Without secondary depo- 

 sit ; true cartilage. 

 With secondary deposit ; 

 bone. 

 C Connectivetissue; tendon; 



5. Fibrous < ligament; elastic tis- 



l_ sue ; muscle. 



6. Fibrmis and cellular Pibro-cartilage. 



(Without secondary de- 

 posit. Vessels. 

 With secondary deposit. 

 Nerve-tubes. 



B. Compound. Glands ; mucous and serous mem- 

 branes ; skin ; synovial membrane ; teeth. 



BiBL. Ucydig, ///■s;'. 18-16; Morel, Hist. 

 18G4 ; KiJlliker, Ic. Hist. 1805; Briicke, £■/<'/«. 

 Organism. ) 'BeolQ, Simple tissues', Exner, 



68 ] 



TISSUES. 



Leitf. thier. Gtncehe, 1873 ; Ranvier, Hist, 

 technique ; Thin, Hist. 1877 ; Schafer, 

 Pract. Hist. 1877; Gibbes, Hist. 1880; 

 Klein and Smith, Atlas Hist. ; Ork, Hist. 

 1881 ; Thierfelder, Atlas path. Hist. 1881 ; 

 Satterthwaite, Hist. 1881 ; Stirling, Hist. 

 1881. 



TISSUES, Vegetable.— The tissues 

 of which vegetables consist are all composed 

 of cellulose sacs or cells, most of them re- 

 taining their primary form, constituting 

 cellular tissue, which makes up the greater 

 mass of plants ; while others undergo com- 

 paratively slight, yet characteristic modifi- 

 cations in form, consistence, and in their 

 mode of union to form other tissues. The 

 tissues may be divided into groups on dif- 

 ferent principles; but for our purpose a 

 simple arrangement will suffice, based 

 chiefly on the character of the compound 

 tissues, leaving the secondary divisions to 

 be determined by the nature of the compo- 

 nent cells. 



Cambium tissue, occurring in the growing 

 regions of all plants having stems, is com- 

 posed of minute cells of variable form, 

 densely filled with protoplasm, and without 

 intercellular passages. It is a transitional 

 structure, forming the first stage of all the rest. 



Parenchyma, or ceUular tissue, is com- 

 posed of cells in which the diameter is 

 not excessive in any one direction, and 

 the walls are comparatively thin. This is 

 divided by authors into many sections, ac- 

 cording to the form of the cells, the laxity 

 of their coherence, &c. The only distinc- 

 tions worth note are between : — 



a. Parenchyma proper, where the cells 

 have polygonal forms. 



b. Merenchyma, where the cells are round, 

 oval : &c. 



c. Collcnchyma, a form of cellular tissue 

 where the walls are greatly thickened 

 with softish secondary deposits ; it 

 occurs beneath the epidermis of many 

 herbaceous plants, in the fi-onds of the 

 larger Algae, of Lichens, &c. 



d. Sdercnchyma. Where the secondary 

 deposit or thickening is hard, as in the 

 bony cellidar tissue of the shells, stones 

 of fruits, Sic. 



prosenchyma. Cellular tissue, usually 

 forming the mass of wood and various 

 fibrous structures, where the cells are atte- 

 nuated to a point at each end, the cells, or 

 fibres, being intercalated and applied side to 

 .side. 



Tela conte.vta. This name is used to 



