A Study of Cerebral Anthropology 37 



rated from the superior temporal gyrus by the sulcus marginalis 

 inferior. The postero-inferior portion of the insula represents 

 the gyrus longus of Henle, the gyrus postcentralis insulae one and 

 two of Retzius, and the pars profunda of Marchand. This por- 

 tion is normally divided into two gyri by a sulcus running parallel 

 to the sulcus centralis insulae, called by Marchand sulcus longi- 

 tudinalis. The boundary sulci of the insula were generally known 

 as the sulcus circularis Reili. Schnopfhagen (1890) called atten- 

 tion to the incorrectness of this name, and Holl (igoSb) went 

 into the embryology of the subject very fully, and showed that the 

 anterior insula was connected to the frontal lobe through the 

 gyrus insulo-frontalis, to the temporal lobe through the gyrus 

 insulo-temporalis, and His had already figured a gyrus insulo- 

 parietalis in a 25 cm. embryo. He found that the gyrus insulo- 

 temporalis persisted in the adult, and extended onto the temporal 

 lobe as the gyrus temporalis magnus. Hence we should say that 

 the boundaries of the insula are anteriorly the sulcus marginalis 

 anterior, superiorly sulcus marginalis superior, and postero- 

 inferiorly the sulcus marginalis posterior. 



There has been a disagreement among anatomists as to the 

 names and morphological significance of the sulci on the surface 

 of the lobe. Marchand divided the insula into three portions, an 

 anterior, a middle, and a posterior or deep portion. He believed 

 that only that portion anterior to the praecentral gyrus was 

 homologous to the anterior portion or anterior insula of apes. 

 Retzius (19020) called the sulcus bounding Marchand's anterior 

 portion posteriorly, the sulcus praecentralis insulae, and the sulci 

 preceding it the sulcus brevis anterior and superior. He named 

 the sulcus of the posterior portion (sulcus longitudinalis insulae 

 Marchand v.d.) the sulcus postcentralis insulae. Eberstaller 

 designated the sulcus in front of the sulcus centralis as sulcus 

 brevis, sulcus brevis accessorius (an inconstant sulcus) and sulcus 

 praecentralis. Holl ( 1908a) proved that Marchand's anterior and 

 middle portions should be considered together as the anterior por- 

 tion of the insula. He (1909), by an extensive series of investi- 

 gations, established the fact that the sulcus longitudinalis (Mar- 

 chand) was the first to develop in the embryo and corresponded 



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