2:^0 Mr. O. Thomas on 



Bogota, it is distinguishable by its more fulvous colour, more 

 uniformly brownish I'cet, longer and narrower nasals, con- 

 nccted parietal ridges, and broader hamular processes. It is 

 also allied to the Central-American species P. centralis, to 

 the dark form of which (subsp. chin'quinus) it bears consider- 

 able external resemblance, though its long narrow nasals 

 form a readily distinguishing mark. 



Proechimys centralis pariamensis^ subsp. n. 



Closely similar to P. c. typicus in size and general colora- 

 tion, but with the head and fore- quarters greyish brown, 

 darker in the middle line, paler on the cheeks and sides of 

 neck, but on both very different to the rich rufous of the 

 back. In typicus the forehead and cheeks are of the same 

 rufous hue as the body. Limbs also greyer than the back. 

 Upper surface of hind feet unifornily brown or with a faint 

 lighter patch on the metatarsus. 



Skull about as in typicus, but the nasals are rather more 

 produced posteriorly, and in all the examples there is a slight 

 irregularity in the posterior part of the parietal ridges. 

 Hamular processes broad and spatulate. 



Dimensions of the type (measured in flesh by collector) : — 



Head and body 2!>7 millim. ; tail 178; hind foot (s. u.) 49, 

 (c. u.) 54; ear 26. 



Skull: basilar length 43; greatest breadth 29; nasals 

 24x6'5; interorbital breadth 13*2; greatest breadth on 

 ridges 23"6 ; length of upper molar series 8" 9. 



llab. Panama. Type from the " Savanna near Panama " ; 

 others from Pocoume, Panama. 



Type. Male. Original number 10. Collected 1st March, 

 1899, by E. Andr^. Five specimens examined. 



Proechimys centralis chiriquinus, subsp. n. 



General colour much darker than in P. c. typicus and pana- 

 mensis, the centre of the back being more spinous than usual, 

 and the dark tips to the spines consequently predominating 

 over the rufous of the hairs. Rump coarsely haired, similar 

 in colour to the rest of the back. Face dark, as in pana- 

 mensis, sides more greyish or greyish brown. Spines of back 

 numerous, coarse, about 1*5 millim. broad and 22 millim. in 

 length. Feet brown, with a slight metatarsal lightening. 



Skull with a broader and heavier muzzle than in the other 

 subspecies ; nasals short and broad ; supraorbital edges very 

 broadly ridged, the ridges running backwards across the 



