8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 39 



The large size of the Escudo specimen, the massiveness, broadness, 

 and heavy ridging of its skull, the inflation of its auditory bullae, 

 and its distinctive coloration all seem to be beyond the possibility of 

 individual variation. This suggests that the Escudo animal is taxo- 

 nomically distinct from mainland populations. That it is conspecific 

 with them is indicated by its alignment with some of the morphologi- 

 cal clines observed in the mainland populations. Wetmore {op. cit.) 

 has named three birds (a wren, a manakin, and a tanager) collected 

 on Escudo de Veraguas that differ from their mainland counterparts 

 in greater size, in addition to differences in color. 



Classification. — The genus Hoplomys is represented by one species, 

 which includes four subspecies : 



HOPLOMYS GYMNURUS GOETHALSI Goldman 



1912. Hoplomys gocthalsi Goldman, Smithsonian Misc. Coll., vol. 56, No. 36, 

 p. 10 (Rio Indio, near Gatun, Canal Zone, Panama). 



Characters. — Size medium ; skull of medium width and ridged ; 

 brain case domed and slightly depressed ; foramen magnum ventrally 

 oriented ; cheek teeth large ; auditory bullae medium ; zygomata con- 

 verging conspicuously anteriorly, and maxillary root tending to flare 

 up slightly from ventral plane of skull ; jugal with hooklike postero- 

 ventral process and small conical posterodorsal projection ; nasals long, 

 narrow, and posteriorly acute ; dorsal spines long and strong ; soft 

 hairs of dorsum appear uniform yellowish orange in mass effect. 



Specimens examined. — Panama : Cana, 2,000 ft., 5 US ; Cerro 

 Azul, 2,100 ft., 14 US ; Ft. Sherman, 4 US ; Gatun, 3 (2 AMNH, 

 1 US) ; Cerro Tacarcuna, 2,650 ft., 6 AMNH ; Rio Cangandi, 200 ft., 

 1 US ; Rio Indio, 2 US. Colombia: Alto Bonito, Antioquia, 1,500 ft., 

 1 AMNH ; Bagado, Choco, 600 ft., 2 AMNH. 



Additional published records. — Colombia : Rio Tamana, branch of 

 the Rio San Juan, Choco (J. A. Allen, Bull. Amer. Mus. Nat. Hist., 

 vol. 35, p. 207, 1916). 



HOPLOMYS GYMNURUS GYMNURUS Thomas 



1897. Echimys gymnurus Thomas, Ann. Mag. Nat. Hist., ser. 6, vol. 20, p. 550 

 (Cachabi, N. Ecuador, alt. 560 ft.). 



Characters. — Size medium or small ; skull narrow and ridged ; brain 

 case domed and slightly depressed ; foramen magnum ventrally 

 oriented ; cheek teeth small ; auditory bullae small ; zygomata con- 

 verging conspicuously anteriorly, and maxillary root flaring up from 

 ventral plane of skull; jugal lacking posteroventral process, but with 



