226 MR. A. H. GARROD ON TOLYPEUTES TRICINCTUS. [Feb. 19, 



large size of the olfactory lobes 1 , together with its general propor- 

 tions, and but little more. 



Our knowledge of the brain of the Dasypodidae has been much 

 increased by a paper from the pen of Prof. Turner in the first 

 volume of the 'Journal of Anatomy and Physiology' 2 on the brain 

 of Dasypus sexcinctus, in which the bibliography of the subject is 

 fully given. 



The general appearance of the brain of Tolypeutes tricinctus differs 

 but little from that of Dasypus sexcinctus, whilst in surface-markings 

 it much more closely resembles that of Tatusia peba, as figured by 

 Rapp 3 , being comparatively simple in its gyration. There is not 

 that difference in the breadth of the anterior and posterior portions 

 of the cerebral hemispheres which is found in Dasypus sexcinctus. 



The Sylvian fissure is only represented by an open and very shallow 

 angle, above which, on the surface of the hemisphere, is a slight, 

 partly encircling, shallow groove of some length, separated from it 

 by a very short distance {vide fig. 2, c). 



Brain of Tolypeutes tricinctus. 



The large olfactory lobes are are much broader than they are deep. 



On the surface of each cerebral hemisphere there are two sulci. 

 One of these, the anterior, is horizontal, and divides the frontal lobe 

 into an upper and a lower part. Its outer extension is nearly to the 

 lateral margin, not going backwards more than one fifth the length 

 of the hemisphere. Internally it ceases on the flat interhemispheral 

 surface as far backward as its outer end (vide fig. 2, a). 



The second sulcus is upon the superior cerebral surface, running 

 from behind forwards and inwards. Posteriorly it commences at the 

 outer posterior angle of the hemisphere a short distance from its ex- 

 Lea formes centrales des Edentates," Nouv. Archiv. du Museum, 1869, 



torn. v. pi. ii. fig. 8 

 s 1807. p. 313. 



3 Eden tn ten, tab. viii. fig. 3. 



