Macalister — On two Forms of Perityphlic Pouches. 215 



On pulling this out, a large pouch, was displayed, hurrowing hehind the 

 psoas muscle as far inwards as the vertebral column opposite the 

 transverse process of the fifth lumbar vertebra, having a strong ilio- 

 lumbar ligament above it, and being crossed at its upper part pos- 

 teriorly by the ilio-hypogastric nerve, and a little lower by the ilio- 

 inguinal. A separate sHp of the psoas muscle from the transverse 

 process of the fifth lumbar vertebra projected into the fundus of the 

 sac. The mouth of this fossa looked upwards, and a little forwards 

 and outwards, and was bounded in part by a crescentic fold of iliac 

 fascia from the anterior surface of the psoas magnus (there was no 

 psoas parvus), passing outwards to the front of the iliacus. So deep 

 was this pouch, that the index finger introduced into it could be im- 

 bedded to the base of the second joint, and could touch the back of the 

 common iliac artery at its bifurcation behind the psoas. Fully three 

 and a half inches of the colon were sunk into this recess, and held 

 there by the reflection of peritoneum from the ascending lumbar meso- 

 colon outwards to the wall of the fossa. The pouch had a distinct 

 flooring of iliac fascia. 



Co-existing in this subject was a good large intersigmoid pouch 

 with, as usual, no fascial relations, but a crescentic fold of fascia formed 

 a shallow retrosigmoid fossa like that described by Leeper. There was 

 a very strong and large cysto-hepato-colic ligament. Fully flve inches 

 of large intestine stretched from the lower lip of the pouch to the 

 fimdus of the caecum, and at the inner side of the pouch the peritoneum 

 was raised and rendered prominent directly internal to the involuted 

 portion of the colon, by the prominent inferior angle of the duodenum. 

 In comparing this case with the already described instances of 

 csBcal fossae, it will be seen to resemble most closely the three cases 

 recorded by A. Biesiadecki of Cracow, in the Untersuchungen aus 

 dem Pathologische-Anatomische Institut in Krakau, Wien, 1872. The 

 fossae, which this author groups under the name fossa iliaco-subfascialis, 

 had this in common with it, that they were bounded by a prominent 

 fold of the iliac fascia, that they were between the psoas and iliacus, 

 that the iliacus muscle was more or less behind it ; his cases were also 

 distinctly beneath the lower edge of the iliac fascia, which was strength- 

 ened by the fibres of the psoas parvus.* A case of caecal fossa is 

 described by Huschke, in which a fold of iHac fascia is referred to ; 

 but this is by no means identical with either Leeper' s pouch or the 

 one described above, as Huschke' s is circumstanced very differently, 

 for this aiithor describes having found, by an exaggeration of the 

 normal descent of the intestine, a falciform fold formed by the perito- 

 neum and the fascia iliaca, very prominent, upwards and forwards, f orm- 



* Even wHen this muscle does not exist as such, a strong band of fibrous tissue 

 strengthens the iliac fascia and passes outwards across the iliacus at its site of in- 

 sertion, while a slip of strengthened aponeurosis lies in the situation of its tendon 

 on the inner side of the psoas magnus. These should be regarded as rudimental 

 organs. 



