Page:A descriptive catalogue of the Warren Anatomical Museum.djvu/117

 fissure is unlike a lateral one, where the two sides of it converge to a point. There was a deep notch in the re- gion of the incisive teeth, but no fissure in the roof of the mouth.

"The inner orbitar processes of the frontal bone had an unusual length ; the nasal bones were wanting, and the ascending portions of the upper jaw met on the median line, thus closing the nasal cavities above. The alveolar border of the upper jaw contained on each side four cavi- ties for teeth, namely, two for molars, one for a canine and one for a lateral incisor, in all eight. The middle incisors were wanting, and their places occupied by the median notch. Behind each of the incisive alveoli are traces of the intermaxillary suture, but that on the right was most distinct.

" A fissure in the upper lip, on the middle line, is quite rare. Leuckart, Vrolik, and Von Ammon have each de- scribed one. The existence of it is admitted by Rokitan- sky, Meckel, and others. Leuckart and Vrolik believe it to be dependent upon, and always co-existing with, a defect of the intermaxillary bone, which opinion is supported by the specimen here described, where the bone in question is partly wanting. (See Vrolik Tabulae ad Illustrandum Embryogenum. Arnst., 1849. TaB. xxxiii. Fig. 7.)

" In the close approximation of the eyes, in the absence of nasal bones, and in the partial deficiency of the inter- maxillary bone, this specimen shows a tendency to cyclop- ism. In cyclopian monsters, in addition to the fusion of eyes and closure of nostrils, there is always absence of the intermaxillary.

" The malformation here noticed is not, properly speak- ing, a fissure in the same sense that the lateral fissures are. There is naturally no fissure on the median line, in any stage of development, since the intermaxillary bud occu- pies the middle and is single, and never subdivided into two portions. If, however, the intermaxillary bud is not developed, the maxillary buds, as they push towards the middle, if they do not reach it, will leave an unoccupied space between them, which will account for the so-called fissure."

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