254 PROCEEDINGS OF THE ACADEMY OF [1888. 



THE PALATAL EUG^ IN MAN. 

 BY HARRISON ALLEN, M. D. 



The structures of the body which are the most constant and 

 those which are the most variable have alike an interest to the 

 biologist and to the physician. When constant they present char- 

 acters which may be employed in classification, and when variable 

 they are accepted as delicate tests for the activity of the nutritive 

 and developmental processes. I propose in the connections last 

 named to study the folds or rugse of the hard palate as they are 

 seen in the human subject after the period of infancy, especially in 

 subjects who have reported to me for the treatment of chronic 

 nasal catarrh. A group of minor structures is here met with which 

 can be presented in a systematic manner notwithstanding the wide 

 range of variation they exhibit. 



What variations from the type met with in the lower animals are 

 seen in man ? How do these variations in turn associate themselves 

 Avith morbid states? With what structures do these variations 

 correlate ? What forces are at work to produce in man results so 

 different from those seen in the animals related to him ? 



I will attempt to answer these questions. I will also give among 

 related appearances those which may have a clinical significance. 



In the main it may be said that the rugse of the lower animals 

 form a constant series. But instances of irregularity can be given. 

 They are much broken up in the posterior part of the palate of the 

 hog. A slight asymmetry often exists in the horse ; and instead of 

 being in opposite, may be in alternate series. For a full discussion 

 of the subject with literature, especially for the description of the 

 human rugse in the embryo and infant, see Carl Gegenbaur. Mor- 

 pholog. Jahrbuch, IV, 673. 



The following embraces a brief description of the rugse in man 

 and a list of names which will be employed in this paper. 



Two kinds of rugse are recognized, the longitudinal and the 

 transverse. The longitudinal lie in the median line and answer to 

 the line of union between the right and left maxillae and premax- 

 illse ; the transverse lie across the palate and are composed of a 

 right and left set. 



The longitudinal kind is divided into two parts, viz. : the raphe, 

 or tiie seam-like line which occupies the middle of the palate at the 



