84 



DR RICHARD J. A. BERRY. 



EoDKNTiA, — Lepus Cujiiculus, the Kabbit. 



All rodents, being herbivorous, possess a cfficum, with the 

 exception of the Myoxidse. In the rabbit there is in addition 

 a well marked vermiform appendix, and the animal is thus 

 peculiarly well adapted for the lines of the present research, and 

 forms an excellent type from which to work. 



In the rabbit the small intestine is, at its lower end, expanded 



Vermiform appendix 



Small Intestine 



Sacculated 

 Colon 



Caecum 



Fig. ]. — Outliue .sc:lieme of the sacculus lotmidus, cfeciim, and vermiform 



appendix of a rabbit. 



into a sacculus rotundus (see figure 1). From this the caecum, a 

 blind diverticulum, is given off, to end in the vermiform appendix. 

 The microscopic appearances presented by the vermiform 

 appendix of the rabbit are very remarkable. They are well seen 

 in Plate VI 1. 1, which has been selected from the many specimens 

 examined as being quite characteristic of its minute structure. 

 In this plate, which represents a transverse section through the 

 appendix, it will be noted that there is a submucous coat, com- 

 posed of large masses of lymphoid tissue, which project into the 

 lumen of the gut in the form of nodular processes. Passing 

 inwards between these, and arching over them, there are ordinary 

 villi. These villi are somewhat clavate at their free extremities, 

 and their margins are either touching each other or nearly so. 

 In this way a series of arches is produced, the concavities of 

 which are occupied by the lymphoid projections from the sub- 

 mucosa. Lymphoid tissue is present to such an extent in the 



