186 BULLETIN 160, UNITED STATES NATIONAL MUSEUM 



Genus GASTROPHRYNE «8 Fitzinger 



1828. Microps Wagler, Isis von Oken, vol. 21, p. 744. [Genotype, Microps 

 unicolor Wagler, idem, p. 744= [7?ana] ovalis Schneider, 1799, Historiae 

 amphibiorum, naturalis et literariae, fasc. 1, p. 131; Microps Wagler pre- 

 occupied by Microps Megerle, 1823, Coleoptera.] 



1838. Stenocephalus Tschudi, M6m. Soc. Sci. Nat. de Neuchatel, vol. 2, pp. 49, 

 86. [Genotype, Microps unicolor Wagler, 1828, Isis von Oken, vol. 21, 

 p. 744 = [iJana] ovalis Schneider, 1799, Historiae amphibiorum naturalis et 

 literariae, fasc. 1, p. 131; Stenocephalus Tschudi preoccupied by Stenocepha- 

 lus Latreille, 1825, Hemiptera.] 



1841. Engy stoma Dum^ril and Bibron, Erpetologie g^nerale, vol. 8, pp. 738, 

 740. [Genotype, [Rand\ ovalis Schneider, 1799, Historiae amphibiorum, 

 naturalis et literariae, fasc. 1, p. 131.] [Nee Engystoma Fitzinger, 1826= 

 Breviceps Merrem, 1820.] 



1843. Gastrophryne Fitzinger, Systema reptilium, fasc. 1, p. 33. [Genotype, 

 Engystoma rugosum Dumeril and Bibron, 1841, Erpetologie gen^rale, vol. 8, 

 p. 744 (des parties miSridionales de I'Am^rique du Nord) = Engystoma 

 carolinense Holbrook, 1836, North American herpetology, ed. 1, vol. 1, p. 83, 

 pi. 11 (Charleston, S. C.).] 



Tliirteen species of tlie genus Gastrophryne were enumerated by 

 Doctor Stejneger in 1910, the northernmost being the Uttle G. caroli- 

 nensis of Southeastern United States and the southernmost Boulen- 

 ger's G. leucosticta from Santa Catharina, Brazil. The 12 American 

 species form a natural assemblage with a rather widespread range, and 

 hence the occurrence of Boulenger's G. borneensis in Borneo has long 

 proved a puzzling obstacle to zoogeographers. This record has often 

 been cited as one of the remarkable instances of discontinuous distri- 

 bution in the Amphibia. A restudy of the type of G. borneensis in the 

 British Museum of Natural History has been made by Doctor Noble,^^ 

 who finds that the internal anatomy of the Bomean species differs 

 from that of the American forms in a number of important details. 

 He has shown that although G. borneensis resembles the species of 

 Gastrophryne externalh'^, the structural features indicate that it is not 

 closely related to the American species, and be therefore proposes a 

 new generic name, Gastrophrynoides, for the species that occurs in 

 Borneo. 



There are in American institutions relatively few specimens of nar- 

 row-mouthed toads from Mexican localities, and lack of adequate 

 material, especially from critical areas, has made it rather difficult to 

 draw any definite conclusions as to the number of species of this genus 

 that may be expected to occur within the boundaries of the Mexican 

 Republic. It is possible that Strecker's G. areolata and Girard's G. 

 texensis may occur in northern Mexico, particularly south of and along 



«' For use of the name Qastrophryne in place of Engystoma, see Stejneger, L., Proc. Biol. Soc. Washington, 

 vol. 23, pp. 165-167, Dec. 29. 1910. 



«« Noble, Q. K., An analysis of the remarkable cases of distribution among the Amphibia, with descrip- 

 tions of new genera. Amer. Mus. Nov., no. 212, pp. 20-23, 1926. 



