MOEPHOLOGr OF THE BE A IX IN THE MAMMALIA. 



0/ J 



size, both absolute and relative, of the optic thalamus. In ihc lowly Metatheroid 



Insectivore Ilacroscelides the dorsal area of the thalamus is little if anv biiraer than 

 the anterior quadrigeminal body. 



Fig 48 '^' 



(a) 



cqp. 



cqa. 



cqp. 



cgp. 



cqp 



C9P- 



cqp. 



A series of diugiiinis rcpie?eiitii)g tlio dorsal surface of the tbalamic and mesencephalic regions in {a) Lemur, 

 (h) Tarsias, (c) Cercopilheais, {d) Fdis, (<>) Frocavia, (/) Lepiis, (g) Dasypvs, and (h) Macrosc elides. All 

 inagnitifd 2 diameters. 



In these respects Lemur distinctly conforms to the peculiar condition of the Primates, 

 and difter.s most markedly from all other mammals. 



It is equally signiticant that in a large-eyed mammal like Lemur the anterior quadri- 

 geminal bodies are so small as they are, not only relatively, but absolutely. They aro 

 certainly much bigger in Tarsius, but in this creature the eyes attain such exceptional 

 dimensions. 



SECOND SERIES. — ZOOLOGY, VOL. VIII. 55 



