98 BULLETIN 43, UNITED STATES NATIONAL MUSEUM. 



bairs In an example measuring 32-™ the parts were marked as above 

 but in addition tlie entire dorsum was uniformly covered witli short olive- 

 brown liair. • +• 



ffahits —Our knowledge of the habits of V. nitidus and its varieties 

 is very scanty. As above stated I think it likely that when all the facts 

 concerning this species and its associates are collected that it will be 

 found that it is very close to, if not identical with the forms now known 

 as V nigricans, V. eUloensis, etc. It is warrantable, therefore, under 

 such'an assumption to include all notes of the habits of these and of 

 specific descriptions of individuals which may be shown to be synony- 

 mous herewith. r,- ^ ^^ 



Y chiloensis in an islandic variety. Bats can readdy take iiight from 

 the mainland to an island of greater distance than Chiloe (vide L.noc- 

 tivigans and Atalapha cinerea). In commenting on the habits of V. chi- 

 loensis Darwin says : " It is not, I believe, common, nor do the humid and 

 impervious forests of that island (Chiloe) appear a congemal habitation 

 for members of the family. It must, however, be observed that even in 

 Tierra del Fuego, where the climate is still less hospitable, and where 

 the number of insects is surprisingly small, I saw one of these animals 

 on the wing." The description and figure of Y. chiloensis Waterhouse 

 (Zool. Voy. Beagle, Mammalia, 1838, 5) answers very well (except that 

 it is without gray color of fur on the inferior surface of the body) to Y. 

 niqricans. Many specimens, which I have examined from California 

 and Oregon, could not be, in the main, better described and dehneated. 

 The dark hues of Y. chiloensis recall those of examples of Y. mtidm 

 which have been collected in Oregon. Is the humid character of this 

 portion of the coast-wise range sufiacient to account for the difference 

 in coloration from the Californiau varieties? It would appear to be 

 true. that the lighter shades of brown and gray are associated with 

 dry hot plains and the darker hues with forests, especially when 

 these cover high hills or humid mountains. Unfortunately nothing is 

 said upon this subject by collectors. The nature of the food, so im- 

 portant a factor in preserving coloration in mammals and birds, is also 

 never vouchsafed. While we know in a general way that the species 

 with its congeners are insectivorous, the kinds of insects selected is un- 

 known From the large numbers of immature forms (as compared with 

 the adult) in theMerriam collection I assume that many were obtamed 

 either from caves or hollow trees. 



Melanic and pedomorphic forms of Y nitidus, as already remarked 

 are common. A careful examination of the materal recently collected 

 by W S Bryant in Lower California, for the Calitoruia Academy ot 

 Science, and by C. Hart Merriam, for the Agricultural Department, has 

 not resulted in bringing the confusion which exists in my mmd respecr- 

 iug Y. nitidus into order. In specimens collected from the btate ot 

 Washington to the lower part of Lower California, the same disposition 

 prevails, namely, to have a bat with a forearm ranging in length Irom 

 30- to 35'" in length; a small, delicate thumb not exceeding 3- to 3^™ lu 



