26 



Anatomy of the Rabbit. 



it is found to yield up to a certain point, beyond which it is tough 

 and resistant. It tends to regain its original shape when the 

 tension is removed. 



Fibrous connective tissue may be greatly modified through the 

 concentration of either one of the fibrous elements. Concentration 

 of white fibres is most common. This con- 

 dition is illustrated in the thick connective 

 tissue layer forming the true skin or corium 

 (Fig. 5), but is more conspicuous in the 

 glistening white tendons (Figs. 7, 34) by which 

 muscles are attached to bone surfaces, in the 

 ligaments uniting bones with one another, 

 and in the thin, broad aponeuroses which 

 serve for muscular attachment. The struc- 

 tures known anatomically as fasciae are 

 special sheets of connective' tissue covering 

 chiefly individual muscles or muscle groups. 

 Concentration of yellow fibres occurs in the 

 dorsal ligament of the neck (ligamentum 

 muchae) where greater elasticity is required. 

 The ligament is not so conspicuous in the 

 rabbit as in larger mammals where the 

 yellow coloration is very noticeable. 



Fat or adipose tissue is a soft form of 

 connective tissue in which the cells are greatly 

 enlarged and contain fatty material in the 

 form of globules. It tends to occur in certain 

 situations and in particular association with the bloodvessels, but 

 otherwise is found in situations where areolar connective tissue 

 might be expected to occur. Special fat masses, sometimes 

 distinguishable by their darker coloration, occur at the side of the 

 neck in the rabbit. In the foetus (cf. Plate VI) large masses of 

 vascular connective tissue are found in this situation, and are 

 probably similar in origin to the storing or hibernating glands of 

 certain other mammals. 



Coloration or pigmentation of certain portions of the body, 

 especially of the skin and hairs, and of the retina, ciliary body, and 

 iris of the eye, is due partly to the presence of special connective 



Fig. 7. From a section 

 of the tendon of origin 'of 

 the biceps muscle: m.f., 

 muscle fibres ending on the 

 tendon; t.. fibrous con- 

 nective tissue of the ten- 

 don. 



