Shufeldt: Osteology of Lasiopyga and Callithrix. 07 



being correspondingly convex in Iront, where theie is a blunt, longi- 

 tudinal crest developed on the median line. At its supero-external 

 angles, short, stoiit apophyses project, each having on its end an articu- 

 lar facet for a rather ong, curved thyro-hyal. Neither cerato-hyals 

 nor epi-hyals are present. 



The Axial Skeleton. 



(Plates XVIII-XIX, figs. 21, 22.) 



THE VERTEBRiE. 



Flower among others has given us more or less full descriptions of 

 the bones composing the skeleton of the trunk in the Primates. In 

 the third edition of his Osteology of the Mammalia, on pages 78 and 79, 

 he presents a table in which is set forth, under the five divisions of 

 the vertebral column, the number of vertebrae found in each division. 

 In the table Homo sapiens is compared in this way with no fewer than 

 thirty-eight species of Apes from different parts of the world. In the 

 list we find five species of Lasiopyga (Cercopithecus), including L. 

 griseoviridis and also Callithrix jacchus. 



In the specimen of L. griseoviridis, the skeleton of which I prepared, 

 the animal had lost about half of its tail either prior to or after capture. 

 Hence this part of the skeleton is imperfect. The tail is perfect in the 

 skeleton of Lasiopyga calUtrichus in the U. S. National Museum, and 

 I have in my own collection a skeleton of C. jacchus in which the tail 

 is perfect. 



In his specimen of Lasiopyga griseoviridis Flower found seven 

 cervical, thirteen thoracic, six lumbar, two sacral, and twenty-five 

 caudal vertebrae. Upon comparing this with the skeleton of L. griseo- 

 viridis at hand, I find it has seven cervical, twelve thoracic, seven 

 lumbar, and three sacral vertebrae. In counting the thoracic verte- 

 brae, I am guided by those which support a pair of ribs, and in count- 

 ing the lumbars, those are included which extend between the last 

 thoracic and the first sacral, — a sacral being understood to be a ver- 

 tebra which articulates with the pelvis and coossifies with one or more 

 vertebrae succeeding it. In Z. griseoviridis three such vertebrae co- 

 ossify to form a sacrum, and following these, every vertebra belongs 

 to the caudal series. 



In the U. S. N. M. specimen of Lasiopyga calUtrichus, No. 16365, — 

 Flower did not make any record for this species, — I find seven cer- 

 vical, twelve thoracic or dorsal, seven lumbar, three sacral, and 



