What may have been a hernia or a relaxation of the transversus perinei was observed in an Undulated Grass Parrakeet (_Melopsittacus undulatus_). A bulge about the size of the finger end was seen externally, beside and behind the anus. This proved to contain several loops of bowel and a mass of fat. A lateral abdominal hernia was seen in a Barbary Turtle Dove (_Turtur risorius_). It consisted of a peritoneal sac and two loops of intestine. This protrusion, while firmly fixed in its unnatural position, was in no way constricted. RECTAL PROLAPSE. Prolapse of the rectum may in a sense be looked upon as a hernia or at least as a relaxation of the anal and perineal muscles with protrusion of parts normally situated intracorporeally. Although not frequent it has been incurable in the animal, as it frequently is in man without operation, a measure we have not adopted. Just what determines weakness in the pelvic outlet is entirely obscure for indeed we have seen here wounds and inflammations of the perineal area without prolapse of the rectum and in none of the cases of prolapse did the pelvic floor seem injured or diseased. It is but speculation to blame the annular muscles of the anus. Tenesmus, or at least reasons for this straining action, have been sought, with the result that in our cases lesions of the egg- laying apparatus in birds and enteritis in mammals have stood out most prominently. In no case have hemorrhoids been encountered nor has a tumor pendant from the colonic mucosa, drawn the bowel toward the anal opening. It might be added parenthetically here that hemorrhoids are practically unknown for quadrupeds, Hutyra and Marek failing to mention them independently and only one reference being found in the _Jahresbericht fur Veterinär Medizin_ (Schmidt 1914–169); this case is more like angioma than hemorrhoids. If tenesmus be active in the production of rectal prolapse then it would have to be assumed that this straining effort can be induced by enteritis since eversion of the rectum has occurred with this disease in the absence of colitis, the condition usually expected in the presence of tenesmus. The thirteen cases have been seen in Mammalia, 8, (Carnivora, 2, Rodentia, 1, Ungulata, 3, Edentata, 1, Marsupialia, 1) and Aves, 5, (Passeres, Picariæ, Striges, Psittaci and Galli each one). Three mammals had enteritis, one had foreign bodies in the bowel and one had many ascarids; three had no demonstrable or suggestive causes. Two of the five birds had enteritis high in the tract, one had uratic calculi in the cloaca, and three had trouble in the egg-laying apparatus: one too large an egg, one a broken egg and one a salpingitis. DIVERTICULA.