192 I. W. BLACKBURN 



dementia, 5 in epileptic dementia, 5 in arteriosclerotic dementia, 

 4 in paresis, 3 in chronic melancholia, 2 in dementia praecox, 

 and 1 case each in manic-depressive insanity, organic dementia, 

 acute delirious mania, acute mania, and idiocy. Twenty-five of 

 these cases were in white males, 11 in colored males, 4 in colored 

 females and 2 in white females. The disproportion between 

 the cases examined of each color and sex makes this of relatively 

 little value. 



T do not see that there can be any special relationship between 

 the mental disease per se and the presence of this anomalous 

 vessel, but on the supervention of arterial diseases some very inter- 

 esting cerebral conditions might be caused. In most instances, 

 cerebral arterial anomalies are compensated for before the develop- 



Fig. o. Diagram of the Circle of Willis with a typical median anterior cere- 

 bral artery. 



ment of the psychosis, the anomaly being then only indicative 

 of ill development. 



In these days of bold operations upon the vessels and even on 

 structures at the base of the brain, it might be well for the surgeon 

 to bear in mind the existence of these anomalies. In fact the main 

 object of the paper • of Grunbaum and Sherrington, quoted from 

 above, was to call attention to the surgical relations of the ine- 

 qualities of cross anastomosis of the circulation in anomalies of 

 this anterior arterial system. Illustrative of these dangers may be 

 mentioned one of my own cases in which thrombosis of the intra- 

 cranial portion of the carotid artery resulted in death of the 



