250 



U. S. p. R. R. EXP. AND SURVEYS ZOOLOGY — GENERAL REPORT. 



epecimens from the Missouri plains and westward. Some of these vary, however, and in most 

 c.ises the characters of wing are more like those of I. viridis, from Pennsylvania. The only 

 constant feature is the greater length of tail in western specimens, which prevails throughout. 

 If there he a specific diiference, it will he based essentially upon the latter feature, upon which 

 the Iclerta longicauda of Mr. Lawrence was founded. His specimen, now hefore me, has the tail 

 rather longer than in any other I have seen, measuring 3.90 inches. A California specimen 

 from Petaluma measures 3.60, or a little less than in No. 39T8. Mr. Lawrence's specimen is 

 in other respects much like the eastern ones, having less white about the sides of the head, less 

 gray on the crown, and less white on the outer margin of first primary than in No. 3975. 



The determination of the name of this long-tailed species (if it be really one) of Icttrta is a 

 matter of much uncertainty. There are three from which to choose: I. velasquezii of Bonaparte, 

 1837, auricollis of 1850, and longicauda, Lawrence, of 1853. Neither velasquezii nor auricoUis 

 are described in a way to indicate any material difference from I. viridis. The former is said to 

 have the under mandible white. If this be found to be a constant character in adult males, it is 

 probable that none of the specimens in the Smithsonian collection belong to it. The description 

 of auricoUis, though not distinctive, will answer very well, especially as the white about the 

 head is mentioned so particularly as to render it probable that it appeared more conspicuous 

 than in the /. viridis, which is really the case in the subject of the present article. As based on 

 a Mexican specimen, it in all probibility is the same with those from New Leon — 3978 — and 

 these identical, as far as I can see, with Nebraska and California ones. Still, as Mr. Lawrence's 

 description is positively applicable to the one bird only^ and Bonaparte's answers almost equally 

 well for both, I prefer to adopt the name of the former, leaving a further examination of the 

 type of auricoUis in the Berlin Museum to settle the question. 



Specimens from Loup Fork, apparently young, (8841-'2,) differ in having the upper parts of 

 a I'ull brownish yellow, occasionally touched with olivaceous. The under mandibles are whitish. 



List of specimens. 



