84 Annals of the Carnegie Museum. 



Plate XIII. 



Fig. 3. Right lateral view of the skull, including the mandible, of Lasiopyga 

 callitrichus. Same specimen as in Plate XII, Fig. i. 



Fig. 4. Right lateral view of the skull, including the mandible, of Lasiopyga 

 griseoviridis. Same specimen as in Plate XII, Fig. 2. Both figures natural size, 

 from photographs by the author. 



Plate XIV. 



Fig. 5. Direct superior view of the skull, mandible removed, of Lasiopyga 

 callitrichus. Same specimen as shown in Plate XII, Fig. i, and Plate XIII, Fig. 3. 



Fig. 6. Direct superior view of the skull, mandible removed, of Lasiopyga 

 griseoviridis. Several incisor teeth missing. Same specimens as shown in Plate 



XIII, Fig. 2, and Plate XIII, Fig. 4. Both skulls natural size, and from photo- 

 graphs by the author. Both of these skulls are from individuals not fully adult, 

 judging from the sutures in the crania, and from the fact that in other parts of the 

 skeletons the epiphyses are not firmly united with the shafts of the long bones to 

 which they belong. 



Plate XV. 



Fig. 7. Direct basal view of the skull of Lasiopyga callitrichus, cf , mandible 

 removed; dental armature complete. Same specimen as shown in Plates XII- 



XIV, Figs. I, 3 and 5. 



Fig. 8. Direct basal view of the skull of Lasiopyga griseoviridis, cf . mandible 

 Removed; three incisor teeth missing. Same skulls as in Plates XII-XIV, Figs. 

 2, 4 and 6. Both skulls natural size, from photographs by the author. 



Plate XVI. 



Fig. 9. Superior view of the mandible of Callithrix jacchus; all the teeth 

 missing. Not fully adult individual; belongs to the cranium shown in fig. 12. 



Fig. 10. Left lateral view of skull, including mandible, of Callithrix jacchus, 

 adult male; dental armature complete. 



Fig. II. Left lateral view of skull, including mandible, of Seniocebus meticulosus, 

 adult male; some of the teeth missing. 



Fig. 12. Superior view of the cranium of Callithrix jacchus; mandible removed 

 (fig. 9); teeth missing; not fully adult. 



Fig. 13. Superior view of the cranium of subadult specimen of Callithrix (sp.?) 

 male. No. 35640, Coll. U. S. Nat. Mus. (Mandible shown in fig. 14.) Died 

 at National Zoological Park. 



Fig. 14. Mandible of Callithrix sp.?, seen from above. Belongs to the cranium 

 shown in fig. 13. 



Fig. 15. Left lateral view of the skull, including mandible, of Aotus miri- 

 quouina. No. 103917, Coll. U. S. Nat. Mus. Dental armature complete. 



All figures natural size and photographed from the specimens by the author. 



Plate XVII. 

 Fig. 16. Antero-oblique view of the skull of Callithrix jacchus (Same as shown 

 in figs. 9 and 12 of Plate XVI of this article). 



