1918] Grinnell: A Synopsis of the Bats of California 249 
II. BASED ON SKULLS AND TEETH 
1. Total number of upper incisors 2. PAGE 
2. Greatest length of skull 30 millimeters or more; upper incisors diverg- 
ing at tips (see pl. 20, fig. 22). * Eumops californicus 370 
2’. Greatest length of skull less than 25 millimeters; upper incisors con- 
verging at tips. 
3. Four teeth in upper jaw behind canine, none minute. 
4. Greatest length of skull 19-21 millimeters. Antrozous pallidus 348 
4’. Greatest length of skull 22-24 millimeters. Antrozous pacificus 352 
3’. Five teeth in upper jaw behind canine, first one minute. 
5. Rostrum louger than wide. 
6. Greatest length of skull more than 22 millimeters. 
Nyctinomus depressus 357 
6’. Greatest length of skull less than 22 millimeters. 
7. Greatest length of skull more than 18 millimeters. 
Nyctinomus femorosaccus 36) 
7’. Greatest length of skull less than 18 millimeters. 
j Nyctinomus mexicanus 361 
od’. Rostrum wider than long. 
8. Greatest length of skull more than 15 millimeters. 
Nycteris cinerea 330 
8’. Greatest length of skull less than 15 millimeters. 
Nycteris borealis teliotis 325 
1’. Total number of upper incisors 4. 
9. Upper incisors completely filling space between canines. 
Macrotus californicus 252 
9’. Upper incisors not completely filling space between canines. 
10. Total number of teeth 32. Eptesicus fuscus 314 
10’. Total number of teeth 34 to 38. 
11. Total number of teeth 34. 
12. Greatest length of skull less than 15 millimeters. 
Pipistrellus hesperus hesperus 305 
Pipistrellus hesperus merriami 311 
12’. Greatest length of skull more than 15 millimeters. 
Euderma maculatum 336 
11’. Total number of teeth 36 or 38. 
13. Total number of teeth 36. 
14. Sagittal and occipital crests well defined (pl. 21, fig. 30, 
pl. 22, fig. 42). Myotis occultus 261 
14’. Sagittal and occipital crests not well defined. 
15. Upper surface of rostrum with distinct depression on each 
side between lachrymal region and external nares. 
Lasionycteris noctivagans 300 
15’. Upper surface of rostrum with no depression on each 
side between lachrymal region and external nares. 
Corynorhinus rafinesquii pallescens 540 
Corynorhinus rafinesquii intermedius 344 
