!i Vli 



Annals of the Carnegie Museum. 



solid and heavy ridge, which posteriorly completely borders the pos- 

 terior nares and more or less interrupts the backward extension of the 

 median pterygoid fossa, on account of the heavy descending processes, 

 while in Po'ebr other iiim the palatine processes unite with the pterygoids 

 in a normal way and form the median pterygoid fossa usually observed 

 in later Miocene camels and in most mammals — i. e., unobstructed 

 posteriorly. While the contention of Dr. Loomis "that the compres- 

 sion of the muzzle by the preorbital and subnasal pits" in Stenomyliis 

 may possibly be a partial cause of the forward position of the post- 

 narial opening, it is also true that these pits on the muzzle of other 

 Miocene camels are similarly located and are deep without having 

 affected either the size or position of the posterior nares; nor is the 

 peculiar consolidation of the vomer, the palatines, the pterygoids, 

 and the presphenoid of Stowmylus, described above, affected in these. 

 The characters above enumerated and discussed are of much impor- 

 tance and, I would say, of quite early origin. Although I believe in a 

 comparatively rapid acquirement of new characters under changed 

 conditions, I do not think that the anatomical features in Stenoniylus 

 as a whole can be disposed of altogether under the plea of especially 

 rapid modifications. I would rather regard the genus a migrant 

 sufficiently modified in order to more successfully live in the same 

 general neighborhood with forms more indigenous to the locality. 

 In my earlier papers upon the genus Stenoniylus I used Oxydactylus 

 for comparison, first, on account of the complete preservation of the 

 type of the latter, and secondly, in order to more graphically express 

 the tylopodan characters in other Miocene forms of which so many 

 are common to Stenoniylus. I plainly stated (p. 300, /. c.) that the 

 genus "should be regarded as the type of a new sub-family," which 

 sub-family Dr. Matthew accepted,^ employiug the name Stenomylince 

 to designate it. In reviewing my first papers describing Stenomylus 

 I am unable to find any statement which could lead Dr. Loomis to 

 say that I placed Stenomylus "near the long-limbed type Oxydactylus'' 

 (I. c, p. 322) except in the sense above stated. 



Note on the Groove for the Extensor Tendon on the Ole- 

 cranon Process of the Ulna of Stenomylus gracilis Peterson. 

 In reading the recent paper by Dr. Loomis upon Stenomylus {Amer. 

 Jour. Sci., Vol. XXIX, pp. 297-323, 1910) I became interested in the 

 'Bull. Amer. Museum of Natural History, Vol. XXVIII, 1910, p. 42. 



