NO. 5 MAMMALS OF PANAMA GOLDMAN IOI 



abundant species, Peromyscus pirrensis, occurring - at the same 

 locality, and points out the more naked tail and shorter ears as dis- 

 tinguishing characters. 



Specimens examined : Mount Pirre, 8 ; Mount TacarcUna, 6. 1 



ORYZOMYS TECTUS TECTUS Thomas 



Bugaba Rice Rat 



Oryzomys tectus Thomas, Ann. Mag. Nat. Hist., Ser. 7, Vol. 8, p. 251, Sep- 

 tember, 1901. Type from Bugaba, Chiriqui, Panama (.altitude 800 feet). 



The two closely allied forms of O. tectus are large, rather robust 

 rice rats with generally rich tawny or ochraceous-tawny upperparts. 

 The underparts vary from nearly pure white to pale buff. The 

 skulls are remarkable for the lateral expansion of the frontals as 

 supraorbital shelves. These forms are typical of a group including 

 O. Havicans and other South American species. O. t. tectus, known 

 only from western Panama and Costa Rica, differs from O. t. 

 frontalis of eastern Panama in the brighter tawny coloration of the 

 upperparts and the more buffy underparts. Aside from the type no 

 specimens appear to have been collected in Panama, but two examples 

 from Boruca, Costa Rica, are assumed to be typical. 



ORYZOMYS TECTUS FRONTALIS Goldman 



Corozal Rice Rat 



[Plate 24, figs. 6, 6a] 



Oryzomys frontalis Goldman, Smiths. Misc. Coll., Vol. 56, No. 36, p. 6, 

 February 19, 1912. Type from Corozal, Canal Zone (altitude 100 feet). 



Oryzomys t. frontalis of eastern Panama is closely allied to O. t. 

 tectus of western Panama, but the upperparts are duller, less dis- 

 tinctly tawny, and the underparts are whiter, less extensively buffy. 

 It is decidedly larger than the related South American forms, O. Havi- 

 cans and O. f. illectus, and differs in cranial details, especially the 

 greater lateral projection of the frontals over the orbits. 



At Corozal the type was trapped in grass and bushes near the edge 

 of a swamp a few feet above sea level. Near Cana specimens were 

 taken at 2,000 feet altitude in an abandoned sugar-cane field where a 

 rank growth of grass and shrubbery was springing up. Here it was 

 associated with the Panama dusky rice rat {Oryzomys caliginosus 

 idoneus), a much more abundant species. Anthony (1916, p. 369) 

 records a specimen from the village of Tacarcuna. 



Specimens examined: Cana, 11; Corozal, 1; Tacarcuna, i. 1 



1 Collection Amer. Mus. Nat. Hist. 



