104 J- Leffingwell Hatch, 



described by Dr. Giovanni Mingazzini, among other peculiarities these 

 conditions also pertained. 



On examining the fissuration of the brain under consideration, 

 I find the following conditions: 



Right hemisphere. Outer surface. — The Sylvian fissure measures 

 7,5 cm. in lenght, the anterior branch which is normal in direction is 

 2,5 cm. long, and it does not extend into the precentrai as in brain 

 No. I described by Dercum. The terminal bifurcations are longer than 

 usual, the vertical one extending along the margin of the ascending 

 parietal convolution for nearly one-third of its length. The general 

 direction of this fissure is from before backwards and from below up- 

 wards at an angle of about 45°. It is average in direction. 



The fissure of Eolando is 8 cm. in length following the deflections. 

 It pursues the usual direction, but is exceedingly tortuous, even more 

 so than those of the other described brains. It extends clear over 

 the margin on to the median aspect of the right hemisphere, and 

 below a very small isthmus separates it from the Sylvian fissure. In 

 the idiots brain described by Mingazzini the fissure of Rolando is con- 

 fluent with the Sylvian fissure. 



The operculum is average in size completely covering the insula. 

 The angle of this sulcus with the great longitudinal fissure is approx- 

 imately 60°. 



The precentrai fissure is comparatively of a uniform upward 

 direction, following closely the course of the fissure of Rolando, although 

 not quite so tortuous. In the lower third of its course there are two 

 short rami given off at right angles. These branches the upper 1,5 cm., 

 the lower 2 cm. in length, are 1,25 cm. apart at their origin and 

 0,5 cm. at their termination; they extend backwards and downwards 

 into the ascending frontal convolution forming a small rhomboidal lobe. 

 The upper extremity of the fissure abuts upon the margin; just before 

 reaching this point, however, it gives off a branch into the substance 

 of the ascending frontal convolution, and one directly opposite into 

 the superior frontal convolution, the peculiar arrangement of fissuration 

 being what Wilder terms zygal. (H = h shaped). 



The first frontal fissure is very tortuous and deep, it also is 



