284 THE GROUSE IN HEALTH AND IN DISEASE 



In the lungs, moulds and streptothrices were almost constantly found. 

 The fact that they were absent in all but a very few of the tubes 



General 



results of sown from other organs indicates that they were really in the 



bacterio- . ... . 



logical e.x- birds' lungs during life, and did not get into the tubes as a result 



of the of contamination. Further, these results have been confirmed by 



observations on a number of other animals, both mammals and birds. 



The other organs and blood were in the immense majority of cases free 

 from cultivatable micro-organisms, except when Bacillus coli was present. 

 Occasionally a single colony of some microbe would appear, perhaps a spore- 

 bearing bacillus like Bacillus suhtilis, or Sarcina lutea, or rarely a mould. 

 On several occasions diphtheroid segmented bacilli were found. That these 

 were sometimes accidental contaminations seems very probable, and in any 

 case their numbers were so few as to be of little practical importance. Never- 

 theless, it may be that some were really in the living tissues during life, 

 and this seems more probable in the case of the segmented bacilli, for these 

 were sometimes found in cultures from the blood, which are less liable to 

 contamination than those from the solid organs, as well as elsewhere. More- 

 over in one case (Grouse 37) they were also cultivated from the contents 

 of the intestinal canal, but were only rarely met with on the exposed 

 agar plates. 



The whole question of the presence of bacteria in the living organs is 

 in course of investigation by us, and we need not dwell further on the 

 matter here, except in so far as Bacillus coli is concerned. 



Beyond the oesophagus, crop, and gizzard the alimentary canal consists of 

 the duodenum, intestine, paired cteca, and rectum (PI. xxxix., Fig. 2). 



The duodenum, a thin-walled light-coloured tube, 4 to 7 inches 



The all- 



mentary long, on which the vessels are clearly seen, forms a U-shaped loop 

 the normal of which the limbs lie in close contact with one another, the angular 

 space on the ventral side being occupied by the pancreas. Next 

 follows the intestine, a thicker walled tube of grey colour some 20 to 34 

 inches in length, and half an inch in diameter. From the junction of the 

 intestine and rectum arise the paired caeca. Each csecum consists of a short 

 narrow portion with small lumen next the intestine, and a long wider portion 

 between 1 and 2 feet, or even more, in length, and about one-third of an 

 inch in diameter. At its distal end it tapers rather suddenly to a point 



' The measurements of the various parts of the alimentary canal vary greatly in dilfcrent birds. 



