210 BULLETIN 144, UNITED STATES NATIONAL MUSEUM 



Pieonyx vivesi Miller, Proc. Biol. Soc. Washington, vol. 19, p. 85, June 4, 

 1906; List North Amer. Land Mamra. 1911, Bull. U. S. Nat. Mus., No. 79, 

 p. 59, December 31, 1912 ; List North Amer. Recent Mamm. 1923, Bull. U. S. 

 Nat. Mus., No. 128, p. 73, April 29, 1924. — McLkllan, Journ. Mamm., vol. 8, 

 p. 243, August 9, 1927. 

 Type locality. — Cardonal Island, Sal si Puedes Archipelago, off 

 San Rafael Bay, Lower California, Mexico. 



Cotypes. — Two females in alcohol. Both originally in Paris Mu- 

 seum; one now in British Museum. 



Distribution. — Islands and coasts of the Gulf of California, Mexico. 

 Diagnosis. — Size and general appearance, apart from the enor- 



Map 13. — Distribution of Pizonyx yivesi 



mously enlarged feet, essentially as in Myotis nvyotis of the palearctic 

 region. Much larger than any known American Myotis^ the forearm 

 about 60 mm. in length. 



Ear. — The ear is rather large ; laid forward it extends about 5 mm. 

 beyond the nostril. In general form it resembles the broad ear of 

 Myotis thysanodes rather than the more narrow type seen in M. veli- 

 fer. About eight faintly defined cross-ridges are usually visible. 

 As compared Avith the ear of M. thysanodes the antitragus is rela- 

 tively larger and the antero-basal lobe is relatively smaller. Tragus 

 more bluntly pointed and relatively shorter than in M. thysanodes, 

 its posterior margin finely but distinctly crenulate. 



