AMERICAN BATS — ^HANDLE Y 109 



Among the vespertilionids it is seen only in Euderma maculatum and in 

 the rare African Glauconycteris superba (Hayman, 1939, 1946), which 

 resembles Euderma maculatum in being black and white but has a more 

 elaborate pattern. Hayman even suggested a similarity of the pattern 

 of Glauconycteris superba to that of the spotted skunk, Spilogale. 

 Some other species of Glauconycteris have a similar pattern but with 

 subdued brown and buff tones rather than black and white. Scoto- 

 manes ornatus of southeastern Asia has a pattern of white spots and 

 stripes on the pelage, but the ground color is bright reddish rather than 

 black. In some other forms, Kerivoula picta and Myotis formosus for 

 example, the flight membranes, rather than the fur, are patterned 

 with contrasting colors (Wroughton, 1912, p. 1195, pi. a). 



Despite numerous evidences of specialization, Euderma retains 

 many primitive traits. It appears to occupy an evolutionary position 

 below the more abundant and more progressive, although less special- 

 ized, Plecotus, with which it shares its geographic range. An early 

 derivative of the Euderma-Plecotus stock, Euderma maculatum has 

 traveled a road of independent specialization to the point where it 

 is possibly overspecialized. 



Genus Plecotus: From the study of Recent and fossil material, 

 I infer that the hypothetical ancestor from which the subgenera 

 Idionycteris, Plecotus, and Corynorhinus were derived probably had 

 the following characteristics: Tooth rows not crowded; I^ bicuspidate; 

 I^ simple, about two-thirds the height of I'; upper canine strong and 

 exceeding P* in height; P^ robust, considerably exceeding cingulum of 

 canine in height; P* with full hypocone surface, a large anterior cingu- 

 lum, and a protocone cusp; M^ and M^ without trace of a hypocone 

 cusp; M^ with prominent metacone and a fourth commissure; lower 

 incisor series strongly imbricated and increasing in size from Ii to I3; 

 lower canine equaling protoconid cusp of Mi in height; Pi much more 

 robust than Pg; P4 double-rooted; lower molars with internal cusps 

 almost equaling external cusps in height. Rostrum narrow and 

 arched; anterior nares not enlarged; supraorbital region sharply 

 ridged; temporal ridges not forming a sagittal crest; zygoma strong 

 and expanded in middle third; basial pits not developed; median 

 postpalatal prominence absent. Nostril with full cornu and lacking 

 posterior elongation; muzzle glands not enlarged; auricle large, with 

 a simple, complete anterior basal lobe, a small accessory anterior basal 

 lobe, and transverse ribs not reaching the posterior margin of the 

 auricle. 



From this generalized or primitive pattern, derivations, either in 

 the form of reduction or simplification or in the form of elaboration, 

 are to be regarded as traits of specialization or progressiveness. In 



