Page:Condor8(6).djvu/17

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?4 8 THE CONDOR [ VoL. VIII This season (1906) has been remarkable for large sets. Out of 10 sets observed in this locality 5 have been of 4 eggs, 3 of 3 and 2 of 2 eggs, all being first sets ex- cept 1 of 3 and 1 of 2. Two sets of 3 each were taken by Mr. B. Carpenter from the same nest, which is unusual, evidently the product of the same birds. If un- disturbed the first of the two sets would uudoubtedly have been 4 eggs iImtead of 3, as in the second set taken a short time later one egg was very much more advanced iu incubatiou than the others. In one set of 4 one egg is very ranch smaller than the rest and is unlnarked. l:'scoJ, dido, (_'a/. The Oberholser Vireo BY JOSEPH GRINNELL N THE CONDOR for September, 1905, pages 142 and 143, Dr. L. B. Bishop de- scribed a new race of the Hutton vireo, uamiug it Fireo hutton/oberho/seri. I must confess that I very much doubted the existcute of any such race. This impression was based ?vholly upon "geographical reasoning," for I had never seen any Huttou vireos from Sau Diego County, whe?me came the type of Bishop's h. oberholseri. I had closely compared my Pasadena series in various plumages with specimens from the viciuity of Monterey, the type locality of ?. h. htdtoni, without detectiug any decided phylogenetic differences; and I reasoued that the very short distance, 130 miles, and general faunal similarity precluded the existence of another distinct subspecies in San Diego County. That good evidence is now at hand proving to my own satisfaction the existence of a race in southern California, differing appreciably from that found around Pasadena and northward, only goes to show that one must not depend too much on "geographical reasoning"; it may be at fault under the best of circumstances. I have before me a male vireo taken at Escortdido, San Diego County, Califor- nia, March 27, 1906, which shows the precise characters pointed out by Dr. Bishop in his description of F. h. oberholseri. Amoug my series of 47 skins of F. h. hnt- toni taken froin Los Angeles County to Siskiyou County there is not oue from which this specimen is not easily distinguishable. It is more leaden-hued instead of greenish dorsally, aud ashlet ventrally. Pasadena birds show a very slight ten- alehey in this direction as compared with Monterey specimens so that iutergrada- tion is probable. I am Judebred to Mr. Jalnes Dixon for the privilege of examining this bird and also a nest and set of three fresh eggs taken with it. A descrip- tiou of these latter is apropos. The nest was located fifteen feet from the ground in the upper foliage of a small live oak growing on a hillside about 150 yards from the big reservoir uear Escortdido. The nest is very bulky, being composed exter- nally of a prodigious quantity of a pale-green fibrous lichen, which is the nmterial invariably chosen for outside liuing by the Hutton vireo, according to my experi- ence. This material is in greater quantity aud looser texture than is ordinarily the case with the Hutton vireo. As usual the nest is suspended by opposite rims from a V-shaped forking of txvigs and surrounded by leaves and staminate flowers of the oak. The lining is of fine round grasses and bits of plant doxvn. The nest is inches in internal diameter, by 1? inches in inside depth; externally 3 by 3