THE COMPARATIVE ANATOMY OF THE INSULA. 

 Tracy Earl Clark, B.S. 



With Plates IX-XIII. 



Table of Contents. 



Introductory Note, ..... 



List of Specimens Examined, 



Historical Sketch, ..... 



The Development of the Operculums, 



Early Development of the Insula, 



The Adult Human Insula, 



Relation of the Insula to the Claustrum, 



The Insula in the Primates other than Man 



The Insula in the Carnivora, 



The Insula in the Proboscidia, 



The Insula in the Rodentia, 



The Insula in the Ungulata, 



The Insula in the Cetacea, 



Summary, ....... 



Synonymy, ...... 



Bibliography, ...... 



Explanation and Description of Figures, 



59 

 60 

 62 



63 



67 

 69 

 73 

 75 

 77 

 82 



83 

 83 

 90 



91 

 93 

 94 

 97 



The importance attached to this region of the human brain 

 and the wide divergence of opinion as to the existence of an 

 homologous area in other mammals led the writer, at the sug- 

 gestion of Professor Burt G. Wilder, to select it in 1890 as the 

 subject for his baccalaureate thesis. The extensive neurologic 

 literature and abundant material possessed by the Anatomical 

 Department of the Cornell University soon convinced the writer 

 of his inability to cover more than the macroscopic side of the 

 subject and that upon a very few specimens. Later the kind 

 offer of Professor Wilder to place at his disposal all of the ma- 

 terial at hand led to the prosecution of the work somewhat 

 further. 



