^4n Introduction to Zoology. 25 



of which we are ignorant, but whicli, though of course not itself organised, 

 makes up, bv its conjunction with similar fibres, organic matter; and which 

 therefore may be said to be alive, since that which is formed by its union 

 is possessed of life.* 



The solid structures of the body may all, by careful maceration, be rent 

 into fibres; the fluids, the proportion of which in the human body is said 

 to be to the solids as nine to ten, when examined beneath the microscope, 

 appear to be composed of globules. 



Membrane is the basis of all the solid structures, and is considered as 

 the simplest modification of the ultimate fibre. It is the most diffused of 

 the textures ; it forms the external and internal coverings, both of the 

 whole body and of its constituent parts ; is the basis of the osseous system, 

 giving form to the bones, and a nidus for the deposition of their earthy 

 secretions : it envelops the muscles, dips down between their fasciculi, 

 encloses the blood vessels and nerves, and forms by far the larger share 

 of the cartilages, tendons, and ligaments. Many of the internal cavities are 

 almost entirely formed of it; as mucous, it lines the mouth, fauces, and 

 alimentary canal, and all other open cavities ; as serous, it envelops the 

 viscera, applies itself to their exterior surfaces, and by its lubricated in- 

 terposition prevents their adhesion to one another ; as fibrous, it forms the 

 capsules of joints, and surrounds the brain of the mammalia ; and as 

 cellular membrane, it forms the cushion upon which the integuments rest, 

 and which gives form and grace to the outline of the figure. We are in- 

 formed byBlumenbach, that so universal is the presence of membrane, that 

 the enamel of the teeth is the only structure in which it has not as yet been 

 detected. The fibres are disposed difi'erently in difierent membranes. In 

 the fibrous membrane, they are not disposed in parallel rows, but are curi- 

 ously interlaced and woven, and such membranes are consequently inelas- 

 tic, and they would otherwise be useless. When elasticity is required, as in 

 the ligamentum nuchse, retractile structure of a claw, &c. the arrangement of 

 the fibres is different, and more nearly parallel. 



The combination of the anatomical principle, which is considered after 

 membrane to be most simple and is most abundant, is muscle, or as it is 

 commonly called, flesh. In whatever other respects, as of firmness, colour, &c. 

 muscles may be dissimilar, they all agree in tliis, that they are fibrous, and 

 admit of being readily torn asunder into fasciculi and subfasciculi, to con- 



• Les anciens croyaient que tous les solides organiques peuvent 6tre ramen^s, en 

 derni^re analyse, ?i une fibre simple ; ils la supposaient form^e de terre, d'huile et 

 de fer. Hallcr, qui admettait cette idee des anciens, convient que cctte fibre n'est 

 visible que pour les yeux de I'esprit : c'est comme s'il avait dit qu'elle n'existe point ; 

 et c'est CO dont pcrsonne nc doutc aujourd'hui. — Magf.ndie, Prec. El. p. 4. 



" InviHibilis est ea ^bra : sola mentis acie distinguimus." — Hali-er, Elem. Phy. 

 torn. II. 



This is a good instance of the prevalence of the slipshod philosophy of that day, 

 which could lead even a man like Hallcr to advance such nonsense. 



No. 1.— Vol. I. K 



