Il6 APPLIED PHYSIOLOGY 



fat will also extend in fine white streaks irregularly in every direction 

 through the meat and can be clearly seen upon its cut surface. 



(2) The fat is deposited in the connective tissue which inclose? 

 separate bundles of muscles. If these bundles are from one eighth to 

 one fourth inch in diameter, and preserve their shape when the finger 

 is passed over them, they contain much connective tissue, and the meat 

 is tough, as in meat from the neck. When a slice of such meat is 

 gently pulled apart, the bundles separate from each other, and are con- 

 nected together by strong, veil-like meshes qf connective tissue. 



On the other hand, if the bundles of muscle are small and not well 

 marked, the connective tissue is small in amount. When a slice of such 

 meat is pulled apart, its bundles do not separate, but the whole piece 

 stretches. 



(3) The cut edge of good beef soon becomes bright red in color. 

 When the connective tissue is abundant between the bundles, it im- 

 parts a paler tint to the meat, and sometimes a bluish tinge. Good 

 pork and veal are pale or almost white in color, but in other points 

 resemble beef (see p. 218). 



Good meat has an agreeable odor and is clean. Excepting as 

 it is marked by connective tissue and fat, it should be of a uniform 

 tint. 



174. Fish. Fish contains albumin about sixteen per 

 cent, fat about six per cent. It is digested with rather less 

 ease than meat, but it can take the place of meat as food. It 

 used to be thought that it contained more nourishment for 

 the brain than other kinds of food, but the brain is nour- 

 ished by the same substances as the rest of the body, and 

 fish is hardly so good for it as beefsteak. 



Fish should always be eaten while fresh, for it is espe- 

 cially liable to decay. 



175. Shellfish. Shellfish, as oysters and clams, contain 

 about sixteen per cent of albumin and three per cent of fat. 

 The large dark mass in their bodies is the liver, which con- 

 tains some sugar. When eaten raw, their own digestive 

 fluids and their livers aid in the digestion of their bodies. 

 When cooked, they require more time and energy for their 



