“…In order to recognize them it is essential that no bowel washout be administered for at least six hours before the examination, as the resultant hyperaemia caused by even so bland a fluid as normal saline will completely obscure them. A good description of these pits has recently been published by Cropper (1945). My only criticism of his excellent article is that I consider a half-strength soap-and-water enema given six hours before a sigmoidoscopy absolutely contraindicated by the resultant hyperaemia.…”