OF ARTS AND SCIENCES. 213 



never interrupted." Ecker* states that the fissure "is never or ex- 

 tremely seldom bridged over in its course by a secondary convolution," 

 and in a foot-note mentions that such an occurrence has never been 

 observed by Turner or Bischoff. The next to report similar cases is 

 Fere,t who has seen two ; in one of them, however, the bridge is sit- 

 uated much lower, and, for reasons to be given later, should perhaps 

 be excluded from this class. ^Ye give his brief account in his own 

 words : " Le sillon de Rolando peut etre interrompu aussi par des plis 

 de passage. Nous avons vu deux cerveaux sur lesquels les deux 

 circonvolutions ascendantes etaient reunis par un pli de passage aussi 

 saillant qu'elles et absolument continu. Sur I'un ce pli etait situe 

 h I'union du tiers inferieur avec les deux tiers superieurs du sillon de 

 Rolando. Sur I'autre il etait situe vers la partie moyenne, de sorts 

 qu'il formait avec les deux circonvolutions ascendantes une II incliiiee 

 en arriere. (Ces deux sujets n'avaient presente aucun trouble intel- 

 lectuel.) " Very recently, Heschl, t of Vienna, comes on the field 

 with a preliminary paper, announcing some of the results of the exam- 

 ination of 1,087 brains, 632 of which were from male bodies, and 455 

 from female. In these he has seen the anomaly six times . three 

 times on the right and twice on the left in male brains, and once on 

 the left in a female one. Heschl has the merit of being the first to 

 explain tlie occurrence of this phenomenon. With the exception of 

 one of Fere's cases, the bridge was always near the upper end of the 

 fissure of Rolando; and Heschl has observed that at about the junc- 

 tion of the middle and upper thirds of the fissure there is very fre- 

 quently a transverse gyrus in its depths, which is not visible till the 

 central convolutions are pulled apart. He has found this in his 1,087 

 brains, when it reached only from one-sixth" to one-third of the way to 

 the surface, 75 times ; when it reached from one-third to five-sixths of 

 that distance, 67 times ; and, as already stated, six times when it was 

 on a level with the surface. Since reading Heschl's paper, the writer 

 has examined a number of brains, and has found several instances of a 

 deep gyrus in this situation. It seems difficult to deny the force of 

 Heschl's argument, that these rare anomalies are instances of uncommon 

 development of this fold. 



This, then, is an anatomical fact of considerable curiosity, that de- 



* The Cerebral Convolutions of Man. 1869. 



t Note sur Qtielques Points de la Topograpliie du Cerveau, par Cli. Fe're. 

 Archives de Pliysiologie Normale et Pathologique. Paris, 1876. 

 i Wiener Medizinisdie Wochenschrift, Oct. 13, 1877. 



