608 



COMPARATIVE PHYSIOLOGY. 



tlie openings to be seen on the surface of the dead bone. The 

 Haversian canals are vascular channels, and the lacunae filled 

 with bone corpuscles (Fig. 446). The marrow in the extremi- 

 ties of the bone is of a red color in consequence of its great vas- 

 cularity; and in the young animal a similar marrow fills the 



Fig. 448.— Section of cartilage of ear of man (Eollett). a, flbro-cartilage; b, conhect- 

 ive tissue. Tlie cartilage had been boiled and dried prior to cutting. 



medullary canal, but later it is less vascular, and abounds in 

 fat. Blood-vessels pass from it into the compact tissue of the 



