PKOCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 483 



cies usually assigned to this genus, as here restricted, that a further 

 subdivision would necessitate a considerable number of generic groups — 

 almost one for every species — so that, upon the whole, it may be better 

 to leave this species in the genus Tijrannus, and cousider it as repre- 

 senting the opposite extreme of size and form from T. magnirostrls. 



The above diagnosis is drawn nj) partly from Dr. Sclater's description 

 of the adult as cited, and in part from an immature female in the 

 Museum of Vassar College, Poughkeepsie, N. Y., collected at Pebas, 

 E. Peru, by the late Professor Orton. 



II. — Descriptions of Xew Races. 



1.— LICHENOPS PEESPICILLATUS, /3. ANDINUS. 



Liclicnops persplcillatns, /3. andiniis, Eidgw. MS. 



Ch. — Similar to L. perspicillaUis {a. perspicillatus), but having the white 

 on the primaries restricted to that i^ortion of the quills beyond the sinua- 

 tion of the outer webs. — Hah. Western South America, from Chili to 

 Xew Granada. 



An examination of the series of Liclienops in the collection of the 

 National Museum reveals a very marked and constant difference between 

 specimens from Buenos Ayres, Brazil, and Paraguay on the one hand, 

 and those from western South America on the other. In the former, 

 of which there are nine adult males before me, representing the above- 

 named localities, the white patch on the primaries extends anteriorly to 

 the end of the primary-coverts, almost the whole extent of the outer 

 webs of the seven exterior quills being of this color, while the shafts 

 are in some specimens pure white throughout; the latter, however ,> is by 

 no means usually the case, but, on the contrary, decidedly exceptional. 

 In the Chilian examples, of which there are three adult males, the black 

 at the base of the primaries, which in the Eastern form is wholly con- 

 cealed by the overlying primary-coverts, extends as far as the sinuation 

 of the edge of the quills, the white being thus restricted to only a little 

 more than half the length of the quills from the ends of the coverts. 

 Only six, instead of seven, of the quills have white on the outer webs ; 

 the shafts are black throughout, while the black on the inner web is 

 increased in proportion with that on the outer. 



A careful measurement of the whole series gives the following result : 



Eastern specimens. 

 Wiug, 3.45-3.65 ; tail, 2.45-2.70; tarsus, 1.0.5-1.12. 



Western specimens. 

 Whig, 3.C0-3.S0; tail, 2.55-2.70; tarsus, 1.05-1.15.* 



I am not able to discover any tangible differences between the females 

 of the two races beyond the larger size of the Chilian examples, the 



* The mimimum is represented by the specimeu from Bogota, except iu regard to the 

 tarsus, which is shortest iu a Chilian examiile. 



