DEVELOPMENT OF THE RECTUM 7 



Ball ('94) describes the columns as lying; wholly within the am- 

 pulla, while on the contrary, Birmingham (in Cunningham's 

 Text-book of Anatomy) shows them as lying wholly within the 

 pars analis recti. Most authors, however, figure them as lying 

 partly within the two portions of the rectum. 



The same is true in regard to the descriptions of the valves of 

 Morgagni and rectal sinuses (sinus rectales) . Some authors show 

 them as very definite structures, closely resembling the valves of 

 the aorta, with wide pockets behind and arranged regularly in 

 between the bases of the rectal columns. Other authors state 

 that they are inconstant and vary greatly in size and shape, and 

 figure them as narrow clefts in between two adjacent columns. 



The rectal columns and valves according to Bodenhamer ('88) 

 were well understood and correctly described by Morgagni and 

 Glisson, and by other early anatomists. 



Bodenhamer gives the credit to Glisson for the discovery of the 

 columns, valves and sinuses. Braun ('01), on the other hand, 

 while admitting that Glisson discovered the valves, states that 

 the columns and 'Sinuositaten' (meaning the smaller secondary 

 sinuses) were discovered and described by Morgagni (1719). 

 Braun further states that Heister (1727) first described the tran- 

 sition zone between the mucous membrane of the rectum and the 

 outer integument. 



Chiari ('78) describes the rectal sinuses under normal and patho- 

 logical conditions. He believes that by an outward and down- 

 ward extension of these structures, fistulae are produced, and in 

 support of his theory he gives several figures of the sinuses in dif- 

 ferent stages of fistulae formation. The same \'iew is held by 

 Bodenhamer ('88). 



The first noteworthy attempt to describe accurately the mucous 

 membrane of the anal region was made by Robin and Cadiat in 

 1874. In describing the junction of the ampulla and the pars 

 analis recti, they state that the latter differs from the former only 

 in that it is not provided with the intestinal glands. The upper 

 limit of the pars analis recti is described as the line where the 

 intestinal glands leave off ('hgne ano-rectale'), while the lower 

 hmit, the iigne sinueuse' lies at a distance of 5 to 8 mm. below 



