Dear Sir, I am much indebted to you for the privilege of inspecting the monstrous-lamb sent by Dr. Pulteney of Blandford, whose laudable interest for the promotion of science, induced him to present it to you. The animal is a male, and apparently at the full period of gestation: its whole frame, excepting the head, is of the natural structure; the deviation in structure of this part, resembles none of the series of monsters which are usually met with among complicated animals. I have preserved the entire skin, in hopes of retaining the outward peculiarities of this creature. According to your suggestion, I took the opportunity, while the subject was in perfect preservation, to examine the brain and its connections: they seem to me very remarkable, and might have afforded matter, to an acute observer, of high interest in the science of physiology, had this monster been yeaned alive. Perhaps it may not be altogether unuseful, to record those internal deviations from the ordinary structure which this dissection presented; and the suggestions arising may possibly excite the attention of some future observer, who may be more happily circumstanced. The head is disproportionably small ; there being no other resemblance to the natural form than in the external ears, which are brought together by their insertions in the front part of the head : the apertures called by anatomists meatus externi, are wanting. Immediately between the insertion of the ears, an opening presents itself, lined with cuticle, and capable of receiving a bougie, the size of the human male urethra : this proved to be the common passage to both the œsophagus and the trachea. The outer surface of the head is regularly clothed with wool ; and there are no appearances of abrasion, or mechanical injury, having taken place at an early period of its formation ; such as are observable in monsters, and perhaps sometimes produced by the rubbing of the umbilical cord, or by the contiguity of the uterine contents, whilst the young animal is yet in a soft state. See Plate IX. Fig 1, and the references.