132 DAVIDSON BLACK 
controversial nature, has accumulated upon the subject of this 
homology. 
Reference to the further work of Elhot Smith (3 to 9) and also 
to the contributions of Zuckerkandl (10 to 13), Kappers (op. 
cit. supra), van Valkenburg (op. cit. supra) and others, makes 
it clear that the crux of this controversy lies in the recognition 
of what constitutes the essential features of the sulcus lunatus 
in apes. Only after these have been established can one broach 
the subject of its homology with the lunate sulcus in man. 
In his report cited above (q. v.), Kappers has considered this 
question carefully, and concludes, with Elliot Smith and Brod- 
mann, that the sulcus lunatus represented in apes by the bottom 
fissure of the deep fossa simiarum, is homologous with the 
fissure of the same name frequently found on the lateral surface 
of the occipital region in man. 
The points, to which I have already alluded, upon which van 
Valkenburg (q. v.) bases his diagnosis of the sulcus lunatus 
may be quoted as follows: 
(1) ‘‘The suleus in question lies somewhat crescent-shaped 
(with its concavity caudad) or more transversal, not far from the 
pole of the occipital lobe;”’ 
(2) ‘“‘In its lateral part terminates a sulcus, that is often 
connected with the first temporal suleus (suleus praelunatus) ;”’ 
(3) ‘‘More or less parallel to it, more towards the front, 
lies a sulcus, into which the sulcus interparietalis terminates 
(suleus occipitalis transversus) ;”’ 
(4) ‘“‘The occipital extremity of the sulcus calcarinus falls 
(whether bent or not round the mantle-side) behind it, and some- 
times extends between two sulci occipitales which are found 
there (these may be connected V-shaped).”’ 
In the above scheme, no mention is made of the relation of 
the sulcus lunatus to the area striata. Indeed this observer 
does not regard the relation of this area to the lunate sulcus as 
‘“‘a point of issue for proving homology,” as Elliot Smith has done 
and it is to this I wish to draw attention. 
As a reason for his opinion van Valkenburg cites the well 
known fact that the stria of Gennari in most cases does not ex- 
