NO. 1494. NOTES ON THE SLOW LEMURS— L YON. 531 



species included under A in the following- key are closely related, and 

 the same is true of those under C and C. 



NachtrieVs name m&nagensis'^'- for a Philippine Lemur, which he did 

 not place in any g-enus, I have not considered, being- unable to obtain 

 further information regarding it than is given in the original descrip- 

 tion,* which is insufficient to determine its generic place, although it 

 probably belongs to this genus or an allied one. 



KEY TO THE SPECIES OF NYCTICEBUS. 



A. Temporal ridges not meeting or approximating each other in old age, but forming 

 two parallel ridges on top of skull; no specimens, not even newborn young, 

 show more than one incisor on each side of upper jaw. 

 B. Mastoid and audital bullae not inflated; half ring of bone forming outer and 

 lower border of orbit, broad and heavy. Underparts whitish. Borneo. 



borneanus. 

 W. Mastoid and audital bullpe moderately inflated; half ring of bone forming outer 

 and lower border of orbit, narrow and light. Tnderparts ochraceous buffy. 



Banka bancanus. 



A^. Temporal ridges meeting or ajiproximating each other in old age, eventually 



forming a sagittal crest on top of skull; most adults show two incisors on each 



side of upper jaw, and young always do. 



C. Lines from crown of head to eyes and ears only faintly marked or obsolete. 



Larger, greatest length of skull less than 63 mm. 



D. Lines from crown of head to eyes and ears practically obsolete; general 



color of head, neck, and anterior part of body clear gray. Siam and 



Cochin China cinereus. 



D''. Lines from crown of head to eyes and ears present but indistinct; general 

 color of head, neck, and anterior part of body not clear gray, mereh^ 

 lighter than general color of upper parts. Eastern Bengal and Burma. 



eoucang. 

 C. Lines from crown of head to eyes and ears well marked and conspicuous. 

 Smaller, greatest length of skull about 58 mm. 

 E. Dorsal stripe bordered on either side, in neck and upper back, by a dis- 

 tinct gray area. Java javanicus. 



E'. Dorsal stripe not bordered on either side in neck and upper back by a 

 distinct gray area. 

 F. General color of upper parts intense and rich; hands, feet, and ears 



dusky. Natuna islands nalume. 



F^. General color of upper parts not so intense or rich; hands, feet, and 

 ears not dusky. 



« In a letter under date of June 7, 1906, Professor Nachtrieb writes: "I can not find 

 out whether that specimen of menagensis ever reached Minneapolis or not -. . . 

 the account of the ' New Lemur ' was not my account . . . Mr. Worcester, I 

 think, was the author "of the account printed . . . the idea of giving a specific 

 name before having determined the generic name struck me as rather odd . . . 

 lost boxes . . . possibly this lemur was in that lot." 



According to the A. O. U. Code the Philippine Slow Lemur (if there is one) can 

 not be considered as having a scientific name. See Canon XXXVIII, where a 

 similar case is cited. 



^Zool. Anzeiger, XV, 1892, p. 147. 



