Watercolor drawing and ink diagram of a case of volvulus of the ascending colon, occurring in a man aged 35 years. The cecum was enormously distended, and occupied the whole of the lower abdomen. The cecum is twisted through one complete revolution, so as to lead to its complete occlusion. There was a long vermiform appendix and a rather voluminous meso-ileum. A volvulus is a subtype of malrotation, in which a loop of bowel is twisted about a focal point along the mesentery attached to the intestinal tract, which may result in a bowel obstruction. Leonard Mark, 1887.