VI CONTENTS 



The Genera Myotis and Pizonyx and tlieir American species — Continued. 



Si^ecies of Myotis occurring in Temperate North America — Continued. Page 



Myotis calif oruicus 148 



Myotis californicus californicus 151 



Myotis californicus cauriuus 155 



Myotis californicus pallidus 157 



Myotis californicus mexicanus 159 



Myotis subulatus 164 



Myotis subulatus subulatus 168 



Myotis subulatus melanorhinus 169 



Myotis subulatus leibii 171 



Species of Myotis occurring in Tropical and South America 175 



Myotis nigricans 175 



Myotis nigricans nigricans 177 



Myotis nigricans extremus 181 



Myotis nigricans nesopolus 182 



Myotis nigricans dominicensis 183 



Myotis chiloensis 189 



Myotis chiloensis chiloensis 190 



Myotis chiloensis dinellii 191 



Myotis chiloensis atacamensis 192 



Myotis chiloensis oxyotus 193 



Myotis chiloensis alter 194 



Myotis ruber 197 



Myotis albescens 200 



Myotis simus 205 



[Myotis pilosus] 208 



Species of Pizonyx 209 



Pizonyx vivesi 209 



Index 215 



ILLUSTKATIONS 



Plate (facing p. 7) 

 [All figures natural size] 



FiGUBE 1. Pizonyx vivesi, Guaymas, Sonora, Mexico. 



2. Large and small cheekteeth in two South American species of 



Myotis {a, M. chiloensis, b, M. nigricans). 



3. Large and small cheekteeth in two North American species of 



Myotis (a, M. velifcr, b, M. lucifugus) . 



4. Maximum size of skull in American Myotis (M. velifer incautus). 



5. Minimum size of skull in American Myotis {M. nigricans domini' 



censis, type) . 



6. Robust general form and well developed sagittal crest {M. velifer 



velifer). 



7. Slender form and slightly developed sagittal crest {M. evotis). 



8. Rostrum large relatively to brain case ; region between canines 



broader than interorbital constriction (M. occultus; No. 137098 type 

 of species, No. 125787 type of M. "baileyi"). 



9. Rostrum small relatively to brain case; region between canines nar- 



rower than interorbital consti'iction {M. albescens). 



