Writes of his observations on the "valves of Houston" in the rectum, which he believes to be rudimentary organs.

Thanks RAV for valuable letter [11232]. CD too ignorant of anatomy to form a decided opinion, but is inclined to attribute spiral folds to reversion and the valves to partial abortion of the fold. Asks RAV to verify by examining lower intestine of an opossum for the structure. If missing he would hesitate to allude to reversion. If RAV can prove the nature of these remnants it would be a conclusion of much interest.