403 



the conclusion seems irresistible — that Treves' method of measuring 

 or defining the caecum is inaccurate. 



Without going into an array of measurements and figures a careful 

 analysis of the apparent and actual caecal measurements, as given by 

 the casts, showed that the latter usually exceeded the former more 

 especially as regarded the length of the caecum proving conclusively 

 that the upper boundary of the caecum is at a higher level than as 

 given by Treves. 



Where the fraenal furrows of Struthers are present they may 

 be taken as absolutely mapping out the upper boundary of the caecum, 

 being as they are, prolongations of the ileo-caecal valve. A careful 

 examination of my series of photographs, will prove, as I have just 

 stated that these fraenal furrows are not always visible from without. 

 We are then left face to face with the problem as to how to distinguish 

 the superior boundary of the caecum when the fraenal furrows are absent. 

 Let me say at once that the solution of that problem can only be 

 approximate, I have proved that the upper boundary of the caecum 

 is higher than Treves would have us believe, therefore when the fur- 

 rows are absent it is safer to take a point midway between the upper 

 and lower borders of the ileum just where it enters the caecum, as 

 representing the site of the ileo-caecal valve or in other words the 

 superior border of the caecum. 



Dimensions of the caecum. 



The dimensions of the caecum are intimately bound up with the 

 previous question ; for naturally, if the boundaries of the caecum cannot 

 be defined, the organ cannot be measured. Given internal measure- 

 ments, the problem is an easy one, for then as Struthers (2) says 

 "the point to measure from is the narrow end of the ileo-caecal 

 orifice". 



With regard to the actual measurements of the caecum there is 

 considerable diversity of opinion. 



In this connection Treves (1) is perhaps the most interesting 

 writer, he says : "From careful measurements made of a large number 

 of adult caeca, I find that the average breadth of this part is 8 cm 

 and the average length 6 cm. The largest caecum that I met with 

 had a diameter of 10 cm, — the smallest on the body of a well- 

 developed woman aged 36, measured only 2 cm in length and 4 cm 

 in breadth. It is exceptional to find a caecum with both its diameters 

 equal." 



26 • 



