THE LARGE INTESTINE 



1171 



little to the medial side of the middle of the inguinal ligament. Less frequently 

 the caecum will be found to be in relation with the iliacus muscle only; or the bulk 

 of it will lie upon that muscle, while the apex rests upon the psoas. In a number of 

 cases the caecum is entirely clear of both psoas and iliacus muscles, and hangs over 

 the pelvic brim, or is lodged entirely within the pelvic cavity. Sometimes the 

 caecum may pass even to the left of the median line of the body. 

 This part of the colon is liable to cons'derable variation. 



Fig. 932. — Interior of the C^cum, Anterior View. (Rauber-Kopsch.) 



— — Plicee semilunares coH 



Frenulum (sinistrum) valvulae coli 



Ostium et valvula processus vermiformis 



Its variations in form may be described under Jour types: 



1. The fcetal type is conical in shape, the appendix arising from the apex, and forming a 

 continuation of the long axis of the colon. The three muscular bands which meet at the 

 appendix are nearly at equal distances apart (fig. 933, A). When the caecum is empty and 

 contracted it tends to approach this type. 



2. The second form is more quadrilateral in shape than the last; the three bands retain 

 their relative positions; the appendix appears between two bulging saccuh, instead of at the 

 summit of a cone (fig. 933, B). 



Fig. 933.- 



-The Four Types of CiECUM. 

 B C 



(Treves.) 



3. In the third type, that part of the caecum lying to the right side of the anterior band 

 grows out of proportion to that part to the left of the band. The anterior wall becomes more 

 developed than the posterior, so that the apex is turned so much to the left and posteriorly 

 that it nearly meets the ileo-csecal junction. A false apex is formed by the highly developed 

 part to the right of the anterior band. This is the usual caecum found (fig. 933, C). 



