﻿40 FIELD AND KOREST. 



as matters of fact." The very first of the exceptions taken, how- 

 ever, is at fault, in important "matters of fact," for it is stated 

 that L. australis is " the most Southern, the smallest and by 

 far the brightest colored.'' 1 As to its being the most Southern 

 of the species of this genus, the very paragraph which Mr. Allen 

 quotes to prove that he "is sustained by Mr. C. E. Aiken," 

 says that " atrata, if anywhere common, must occupy a still more 

 Southern locality !" As to its being the smallest, the measurements of 

 106 specimens, compared with Mr. Allen's own exhibit of measure- 

 ments of almost as many (94) fresh specimens of tephrocotis and littora- 

 lis prove that australis averages .02 of an inch more in length of the 

 wing, and .32 more in length of the tail, than the average of the two 

 more Northern, (and, as Mr. Allen's theory Avould have it, consequently 

 larger forms ! 6 Neither is it the most brightly colored, for any one 

 of the four other forms is equally bright when specimens of correspond- 

 ing season are compared. In this connection, Mr. Allen should re- 

 member that he compares australis in its greatly intensified midsummer 

 dress with tephrocotis and littoralis in their dull winter livery. [See 

 remarks under head of "Seasonal variations," pages 59, 60 of my. 

 monograph.] As to L. tephrocotis, it is stated: " Climatologically 



5 I have elsewhere alluded [See American Naturalist, Vol. vii, Sept., 1873, p. — ,] 

 to the tendency of our author to form hasty conclusions regarding the relationship 

 of certain congeneric forms, by which was meant the toofrequent unfortunate 

 selection of examples supposed to illustrate "laws" of variation, the present 

 genus being a case in point. Such slips, even in the absence of any real 

 objection to the theories under discussion, are calculated to make one extremely care- 

 ful not to accept without due confirmation by investigation, the "laws" which Mr. 

 Allen endeavors to establish — however plausible they may seem when viewed from 

 the author's standpoint. The pages of Mr. Allen's works abound with errors of this 

 kind, which, unless corrected, can only involve the subject in confusion by rendering 

 it extremely difficult for the student to sift from the heterogeneous mass of argument 

 the positive t7-uths, which to the exclusion of mere theory, are needed as the basis of 

 true laws of variation. A few examples of these hasty conclusions j may be quoted as 

 exceedingly pertinent to the subject in hand : 



On page 320 of the "Mammals and Winter Birds of East Florida," the Western 

 Rough-legged Hawk, (Archibuteo ferfugineus,) is mentioned as the "Archibuteo 

 ferrugineus type of the A. lagopusP This statement would, doutless not have been 

 made had the two species been compared ; this seems not to have been done, however, 

 hence the less excuse for the " thegreat positiveness " of the statement. On page 329 

 of the same work, " Btiteo oxypterus," Cassin, is referred to B. pennsylvanicus, with 

 as much confidence as if the type had been actually examined. On page 306 we are 

 informed that Floridan specimens of Centurus carolimts " seem to accord in every 

 particular with the so-called Centurus subelegaus of Lower California and Mexico " — 

 a distinct species, which, by the way is not known to occur in any part of Lower Cali- 



