ALLEN: mammalia: VESPERTILIONIDyG. 1 89 



in Paraguay, and avowedly based on Azara and Rengger, evidently mainly 

 on the latter ; the other, his Atalapha bonaerensis, as found in Argentina, 

 and based on Argentine specimens. He says that the latter is one of the 

 largest and handsomest species found in the Republic of Argentina, and 

 gives its spread of wings as 14 inches, as against 10 to 11 in his A. vil- 

 losissima. This would seem to indicate that his bonaerensis could not be 

 a form of the L. borealis group, were it not that the "envergure" is incon- 

 sistent with the other measurements, thus implying an error. 



Mr. Thomas has referred Lesson and Garnot's bonariensis to L. borealis, 

 as Lasiurus borealis bonariensis (Ann. and Mag. Nat. Hist. (7), VIII, 

 Nov., 1901, p. 436), adding : "The Red Bat was not observed by Azara, 

 his Chauve-souris septieme, the basis of Vespertilio villosissinuis, Geoff, 

 being clearly a southern representative of the Grey Bat {Lasiiirns cinerens, 

 P. de Beauv.)." 



A few weeks later, in calling attention to the apparent identity of Les- 

 son and Garnot's Vespertilio bonariensis (1820) with E. Geoffroy's Vesper- 

 tilio villosissimus (1807), I incidentally said (Proc. Biol. Soc. Wash., XIV, 

 p. 184, Dec. 12, 1901): "That Azara's Chauve-souris septieme is not ref- 

 erable to the Lasiurus cinerens group, as stated by Mr. Thomas (Ann. 

 and Mag. Nat. Hist. (7), Vol. VIII, Nov., 1901, p. 435), is evident from its 

 small size, which barely equals that of an average example of L. borealis."' 

 A few months later Mr. Thomas returned to the subject [ibiil., IX, April, 

 1902, p. 238, footnote), as follows : " I can by no means accept Dr. Allen's 

 recent alteration of my identification of Azara's ' Chauve-Souris septieme' 

 from the local race of Lasinriis cinerens to that of L. borealis, a determina- 

 tion I came to after most carefully weighing the claims of the three Para- 

 guayan Lasiuriio this doubtful honour. I freely grant that the ' envergure ' 

 given by Azara (313 millim.) is a good deal below the corresponding 

 dimension in fresh and well-stretched specimens of L. cinerens; but if 

 Azara's specimens were a little dry and stiff, or immature, the discrepancy 

 would easily be made up, while nothing will give any specimen of L. 

 borealis an ear-length of 15 millim. . . . But the primary point is the 

 coloration. With such conspicuously different and brilliantly colored 

 bats as L. cinerens and borealis the first thing that would strike any, and 

 especially any non-technical, observer is the hoary or whitish-washed 

 colour of cinerens and the brilliant rufous of borealis. Now Azara says 

 ' le poil est . . . d'un brun tr^s-blanchatre,' an expression perfectly appli- 



