94 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 69 



Genus ZYGODONTOMYS Allen. Cane Rats 

 The geiuis Zy^odontomys includes medium-sized, ground-inhabit- 

 ing rodents which are grayish-brown in general coloration, with tails 

 shorter than the head and body. The members are similar to 

 Oryzomys in external appearance, but may usually be distinguished 

 by the proportionately shorter tail and shorter hind feet. Recourse 

 to the skull may, however, be necessary in order to make accurate 

 determinations, generic distinction being lodged mainly in dental 

 details, especially the absence of distinct style and stylid ridges and 

 the presence of straight, antero-posteriorly directed commissures in 

 the molar crowns. In Panama Zygodontomys superficially resembles 

 the cotton rat, Sigmodon, but the ears are smaller and the light and 

 dark elements of the pelage, more finely mixed, produce a less 

 coarsely grizzled combination of color. 



ZYGODONTOMYS CHERRIEI CHERRIEI (Allen) 



Cherrie's Cane Rat 



Orycoinys iherriei Allen, Bull. Amer. Mus. Nat. Hist., Vol. 7, p. 329, 

 November 8, 1895. Type from Boruca, Costa Rica. 



The range of Cherrie's cane rat extends from Costa Rica into 

 Panama where it was first recorded by Bangs (1902, p. 37) on the 

 basis of a young example collected by W. W. Brown, Jr., at Bugaba. 

 He says : " I have compared this example with topotypes, kindly 

 loaned by Ur. Allen and can find no differences." The species was 

 noted by Thomas (1903a, p. 40) from Cebaco Island, near the coast 

 of Chiriqui, whence it was sent by J- H. Batty. Allen (1904, p. 69) 

 lists II specimens taken at Boqueron by the same collector. 



Zygodontomys cherriei is replaced in the Canal Zone by Z. c. ven- 

 triosus, a larger, paler animal, with the back more uniform in color, 

 less distinctly darkened along the median line. 



Specimens examined : Boqueron, 1 1 "; Bugaba, i ' ; El Banco, i. 



ZYGODONTOMYS CHERRIEI VENTRIOSUS Goldman 



Canal Zone Cane Rat 



Plate 23, figs. 3, 2^0 



Zygodontomys cherriei ventriosus Goldman, Smiths. Misc. Coll., Vol. 56, 

 No. 2>^, p. 8, February 19. 1912. Tj-pe from Tabernilla, Canal Zone, 

 Panama. 



The Canal Zone form of Zygodontomys cherriei is closely allied 

 to the typical form, Z. c. cherriei, but is larger and paler in color, 



* Collection Amer. Mus. Nat. Hist. 

 'Collection Mus. Comp. Zool. 



