Paracephalus

(par-as-ef -al-us), head. I. A species of omphalosite monsters, characterized by the presence of four extremities, more or le imperfect, especially in the digits, an imperfectly formed head, a rudimentary condition of the viscera, and, occasionally, absence of the heart. The paracephalus is one of unioval twins, the sex being always the same, and usually female. It is incapable of living. 2. A variety of the foregoing species in which the head is very imperfectly-formed, more or le defective in all its parts, but exhibiting rudiments of the cranium and of the organs of sense, and po e ing even an oral orifice and a buccal cavity. The trunk is also defective, and there are no superior extremities.