765 



always occur when a tube passes off from another tube or cavity at 

 an acute angle." As the appendix usually leaves the caecum at an 

 acute angle it thus produces a sharp concave edge or "more or less 

 of a semilunar membrane" (Struthers). 



With regard to the possibility of the valve obstructing the flow 

 of matter to and from the appendix, Struthers adds that "when the 

 fundus of the caecum is full, or when the body lies on the back or 

 on the left side, there is nothing to prevent semifluid caecal contents 

 raising the valve and passing into the appendix". 



Personally I am inclined to agree with the later authors and 

 regard Gerlach's valve as an inconstant structure and of no import- 

 ance whatever. 



4) Intra-abdominal Positions of the Appendix. Refer- 

 ring to this point Talamon (13), says "regarding the position of the 

 free end and its relations to surrounding organs, they are far from 

 being always the same". Talamon's statement is certainly an obvious 

 truism to judge from the writings of others, as nothing could be more 

 extraordinary than the diversity of opinion upon this point. What 

 Treves, for example, regards as the normal or least variable intra- 

 abdominal position of the appendix, another author looks upon as 

 almost abnormal, and so on. The fact is, that the positions of the 

 appendix within the abdomen are so variable as almost to defy classi- 

 fication; as I have elsewhere remarked, their only certain feature is 

 their uncertainty (14). If I might attempt any classification at all I 

 should say that the following is at once the simplest and the least 

 unreliable : 



1. The Pelvic Position. 



2. The Retro-caecal Position. 



3. The inward Position (Pointing towards spleen). 



4. Variable. 



The terms sufficiently explain themselves and the positions are 

 given in what is probably their order of frequency. More than this 

 should not, I think, be attempted nor should figures be given as the 

 vermiform appendix has no set or stereotyped position within the 

 abdomen. 



5) Relations of Appendix to Caecum. Here we have 

 much more constant data to work upon, and it is a somewhat singular 

 fact that while so much has been written upon the ever shifting and 

 therefore worthless intra-abdominal relations of the appendix generally, 

 little or nothing has been done with regard to the caecal origin of 

 the appendix. These errors of omission are all the more remarkable 



