62 Journal of Comparative Neurology. 



historical sketch. 



Vicq d' Azyr (le, 1786) seems to have been the first to 

 call attention to this area in the human brain. He refers 

 (Pt. II, p. 26) to it as " the convolutions situated between the 

 Sylvian fissure and the corpus striatum " and again (Pt. II, 

 p. 74) as "the convolutions which accompany the Sylvian fis- 

 sure." These references would seem to indicate that at that 

 time all that was known was the fact of the existence of certain 

 gyres in that region which, on account of their concealed posi- 

 tion, had attracted but little attention ; furthermore these are 

 the only references made to this region in his volume of sev- 

 eral hundred pages. 



Monro (42, 1788) pictured three gyres of the human in- 

 sula seen after the removal of the ventral portion of the cere- 

 brum, but he neither named nor described them. 



Hence it remained for Joh. Christ. Reil (1804- 1806) to 

 give the first description as follows: "Die Insel hat eine 

 langlichrunde Gestallt. " Since that time the area has been 

 known as the "insula" or "island of Reil," although many 

 other names have from time to time been applied to it (see Syn- 

 onymy, p. 93.) 



The insula seems to have attracted little attention during 

 the next half century and it was not until about i860 that the 

 study of cerebral localization caused increased importance to be 

 attached to it. Until several years later it was supposed that 

 the insula governed, at least in part, the power of articulate 

 speech. Authors had noted that in aphasics there was gen- 

 erally a lesion of the (nsula and the left subfrontal gyre. They 

 seem not, however, to have taken account of lesions confined 

 strictly to either area and they assumed that the insula had been 

 first affected and that later the lesion had extended into the ad- 

 joining area. Broca ( 4 ) disproved this. By comparing the 

 lesions found in postmortems upon a large number of aphasic 

 patients he reached the conclusion as early as 1861 that the 

 faculty of speech was located in the left subfrontal gyre, still 

 often called " Broca's convolution." During the next seven 



