DEPOSITS ELSEWHERE THAN IN SOUTH AFRICA. 353 



For the generic distinctness of Brithopus he specially urges the 

 presence of a second perforation or canal, near the upper part or 

 beginning of the supinator crest, which canal he calls the foramen 

 condyloideum externum, and conceives that it may have served for the 

 passage of the arteria radialis *. This canal, Kutorga states, had 

 not been previously observed in the humerus of any vertebrate ani- 

 mal ; and at that date (1838) the statement was true. 



I may not be mistaken in supposing that the reduced copy of 

 Kutorga's figure of the above-defined Permian fossil will be accepta- 

 ble, to which I have added (Cut, fig. 1) letters indicative of the 



Fig. 2. 



i 



Fig. 1. 

 Fig. 1. Brithopus priscus, Kut. Fig. 2. Orthopus primcevus, Kut. 



same parts as in figs. 6-11, pi. xi., Quart. Journ. Geol. Soc. vol. 

 xxxii. The significance of the foramen marked m will thus be 

 appreciated. 



Kutorga finds evidence of a second mammalian genus in another 

 fossil from the same locality and formation, which he describes and, 

 fortunately, figures in the same treatise f . Conceiving this fossil to 

 be the lower portion of a humerus, with also the characters of the 

 foramen condyloideum internum, he indicates differences which support 

 his conclusion that it formed part of a distinct mammalian genus 

 and species, for which he proposes the name Orthopus primcevus. 



* " Die Basis dieses Kamrnes ist schrage von oben nach unten mit einem 

 cylindrischen Kanale durchbohrt, der in seinen beiden Enden in flachorale 

 Gruben ubergeht, und eine Arterie, wahrscheinlich die arteria radialis, im 

 oberen Theile ihres Verlaufes beherbergte." — lb. p. 11. 



t Op. cit. p. 15, Taf. ii. 



