88 



DR RICHARD J. A. BERRY. 



wall is filled by lymphoid tissue, and that this lymphoid tissue 

 ceases with great abruptness at the junction of cfficum with 

 large intestine. 



It will be very evident that the three types examined yield 

 singularly uniform results. In all of them, the true cffical apex 

 is characterised by a preponderance of lymphoid tissue. In all, 



Caeca 



The two short 

 Caeca 



Transverse Section 



Fio. 2. — Diagrammatic scheme of the large gut and two short Cfeca of a pigeon. 

 Shown in longitudinal and transverse sections. 



this lymphoid tissue is present at the csecal apex in much 

 greater amounts than in the rest of the alimentary canal ; and 

 in the two whose developmental history has been followed, this 

 lymphoid tissue reaches its maximum development within one 

 week after birth. 



With these data, the results obtained from the other animals 

 examined may now be compared. 



Pisces and Amphibia. 



Specimens of the intestinal canal of both the skate and the 

 common frog have been examined, but did not show any evi- 

 dences of lymphoid tissue. It may be incidentally remarked, 

 with all due caution, that lymphoid tissue would not appear to 



