74 MAINE STATE COLLEGE 



-we fail to discover any indication that the unlike rations have 

 caused unlike growth of tissues. 



(4) Percentage composition of the carcasses (dressed beef.) The car- 

 casses have the same similarity of composition that the entire bodies 

 do. Comparing- the dressed beef from the steers of the same age we 

 find essentially the same proportions of water, ash, protein and fat. 



We observe here as in the case of the entire bodies that the older 

 and more mature and fatter animals furnish beef with a smaller pro- 

 portion of water and protein and a larger proportion of fat than the 

 younger animals do. 



(5) Composition of the edible portion of the carcasses. This includes 

 in these cases all of the carcass but the bones. Some other material 

 is not edible, such as certain connective tissues (tendons, cartilage 

 &c.) and which would find its way into the kitchen refuse. The 

 bones were all the non-edible portion, however, which it was easy to 

 separate, and the proportion of edible material is not greatly too 

 larg-e. We still fail to find that the unlike rations have caused es- 

 sential variations in the proportion of water or of any class of eon- 

 stitiients in the flesh of the animals. As noted with the dressed 

 beef, the edible parts of the carcasses of the older and maturer steers 

 contain smaller proportions of water and protein and larger propor- 

 tions of fat than is the case with the younger animals. This fact, 

 though not new, endorses the popular belief that "young" beef does 

 not "spend" as well as that from maturer animals. 



The writer is obliged to confess that he is surprised at the out- 

 come of the investigation under discussion. He had expected that 

 the ration with a liberal supply of protein would cause a more gen- 

 eroiis development and proportion of muscular tissue than the other 

 ration generally regarded as somewhat deficient in protein, and that 

 the latter ration would produce animals relatively richer in fat. This 

 expectation is not realized. While the protein-rich ration did for 

 a time cause more growth than the other, Ave are unable to discover 

 that it was different growth. 



The flesh of the animals which ate the ration relatively poor in 

 protein did not differ in general appearance from that of the other 

 animals, and a chemical analysis does not show any essential differ- 

 ence in the proportions of protein and fats. 



This investigation adds materially to the facts previously known 

 which go to show that the individual animal possesses a consti- 

 tutional inertia which may not easily be overcome. It is, perhaps, 

 only when we resort to extreme measures, that Ave are able to dis- 

 turb the methods of growth to Avhich the animal by breeding is 

 committed. It appears that though the ration varies Avidely. an ani- 

 mal selects from it and assimilates, such materials as suit the needs 

 and purposes of that particular organism, and that while the rate of 

 production may be A T ery much modified by the character of the 

 ration, the kind of production, AA'hether of meat or of milk, is chiefly 



