278 



SCIENCE. 



[N. S. Vot. XXII. No. 557. 



mating of H. chrysopiera with H. pinus, but 

 in the first of these, as will presently appear, 

 the male parent is hypothetical. It is to be 

 noted that in the first case Dr. Fisher found 

 a female H. chrysoptera feeding a young H. 

 pinus in a cedar tree. Upon the shooting of 

 this fledgling the old female flew away; the 

 shot startled another young bird from some 

 bushes near by, and as it flew the female also 



and I succeeded in wounding the female only and 

 had to follow and kill her with a second shot. On 

 my return to the place where I first shot at her, 

 I could not find the young one, nor did a careful 

 search disclose it. In advancing for a nearer 

 shot I had a good opportunity of seeing the young 

 bird: it closely resembled its mother in appear- 

 ance and had no yellow on the breast, whereas the 

 one killed was the exact counterpart of the young 

 of the blue-winged yellow warbler, with its yellow 

 breast and white wing-bars. In all probability 

 the father of this interesting family was a speci- 

 men of Eelminthophila pinus." 



This is the entire account of the incident. (W. 

 E. D. S.) 



' The Interbreeding of Eelminthophila pinus and 

 E. chrysoptera,' by John H. Sage, Portland, Conn. 

 "On June 13, 1889, Mr. Samuel Robinson, who 

 has collected with me here for the past fifteen 

 years, noticed a male Eelminthophila pinus, with 

 food in its bill, fly and disappear at the foot of 

 a small alder. A female Eelminthophila chrysop- 

 tera soon appeared, also with food, and was lost 

 to sight at the same spot as the other bird. On 

 going to the locality five young birds flew from the 

 nest and alighted on the bushes in the immediate 

 vicinity. Both parent birds were soon feeding 

 the young again. He shot the old birds and se- 

 cured all the young, which, together with the nest, 

 are in my cabinet. 



" * * * The male (pinus) is a very bright 

 specimen with white wing-bars, edged with yel- 

 low. The female [chrysoptera) is strongly 

 marked with yellow below, the wing-bars being 

 exceptionally rich with the same color. 



" The young, two males and three females, are 

 all similar, and have the head, neck, chest, sides 

 and back olive-green. Abdomen olive-yellow. 

 Remiges like adult pinus. Two conspicuous wing- 

 bars of light olive edged with yellow." 



This is the entire account of the incident, ex- 

 cept a description of the locality, the nest and its 

 situation. (W. E. D. S.) 



flew and alighted near it and was then shot. 

 The young bird that was killed ' was the exact 

 counterpart of the blue-winged yellow warbler' 

 (H. pinus), while the second bird carefully 

 observed resembled the adult bird that was 

 shot, and was, therefore, apparently a young 

 H. chrysoptera. No male parent was seen 

 nor were any other young observed. 



Granting that both of these fledglings were 

 the progeny of the bird seen feeding one and 

 associated with the other, and also granting 

 that the unknown male parent of both these 

 young birds was H. pinus, neither of the 

 young was H. leucohronchialis, the hybrid 

 which it is asserted is the result of such a 

 union. 



The second case which is recorded by Mr. 

 Sage goes on to state that a male H. pinus 

 and a female H. chrysoptera were discovered 

 feeding five young in a nest; these birds flew 

 out of the nest on being approached, where- 

 upon all seven were collected. The author 

 says that the male was typical pinus and the 

 female typical chrysoptera, ' strongly marked 

 with yellow below.' The five young proved 

 to be two males and three females and ' are 

 all similar,' being olive green in color, becom- 

 ing olive yellow on the abdomen and having 

 the wings like young pinus. Surely these 

 young are not leucohronchialis, and while the 

 interbreeding of chrysoptera and pinus is 

 hereby thoroughly established as a rare and 

 casual occurrence, these hybrid young, the 

 result of this union, so far as I can perceive, 

 are a direct refutation of the hybrid theory, 

 which attempts to account for the origin of 

 H. leucohronchialis. 



On the other hand, we have direct evidence 

 that both H. leucoironchialis and the rarer 

 H. laivrencei have mated and bred and reared 

 young with H. pinus. 



In view of the foregoing facts, I am of the 

 opinion that in H. 'leucohronchialis and in 

 H. lawrencei, presently to be considered, we 

 have examples of two separate and distinct 

 ' mutations ' from a common parent stock or 

 species. That is, I believe that H. pinus, 

 early in the last century became unstable as 



