'1886.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 521 ^ 



ON A PROBABLE HYBRID BETWEEN DRYOBATES NUTTALLH 

 (GAME.) AND D. PUBESCENS GAIRDNERU (AUD.). 



By ROBERT RIOOlTAir. 



No. 39456, U. S. National Museum collectiou of birds, is labeled and has 

 always passed for, ^'■Picus nuttallii f^ but a recent critical examination of 

 the extensive series of that species and its several allies in the national 

 collection has resulted in the discovery of such a number of abnormal 

 characters possessed by the specimen in question as to lead irresistibly 

 to the conclusion that it cannot be referred, without qualification, to 

 that, nor, indeed, to any other known species. That it is a new or dis- 

 tinct species is very strongly discredited by the circumstance that ia 

 every character wherein it departs from the diagnostic characters of D. 

 nuttallii it agrees with D. pubescens gairdnerii — every feature of size, 

 form, and coloration being exactly intermediate between the two, and 

 thus justify the theory of its being a veritable hybrid between the two 

 species. In order to render this more clear to the reader the facts may 

 be tabulated as follows: 



Measurements. 



Coloration. 



Crown 



Ked occipital patch. 



D. nuttallii. 



Black, conspicuously 

 streaked with white. 



.70-.75 wide at widest 

 part. 



Back i Keffularly barred with 



black and white, the 

 bars of the former color 

 rather broader. 



Middle wing-coverts . 



Greater wing-coverts . 



Conspicuously spotted 



with white. 

 Cro8,sed by two rows of 



large white spots (the 



first concealed by 



middle coverts). 



Supposed hybrid. 



Black, with a few white 

 streaks, next to red oc- 

 cipital patch. 



.70-.80 wide at widest 

 part.* 



Irregularly barred and 

 transversely spotted 

 with white, the white 

 bars considerably 

 broader than the black 

 ones, and anteriorly 

 broken or modified into 

 large spots, some of 

 them longitudinal in 

 direction. 



Plain black 



The three or four middle 

 feathers each with one 

 small white .spot, the 

 rest plain black. 



D. gairdnerii. 



Entirely uniform black. 



.30 wide at widest part. 



Broadly striped dowt 

 middle with white. 



Plain black. 



The two middle feathers 

 each with one small 

 while spot, the rest 

 plain black. 



* The apparently greater width of the red occipital patch in the supposed hybrid than in D. nuttallii 

 is no doubt owing to the diflierent position of the head in the two skins, that of the former having the 

 head bent at a right angle to the body, while the latter has it straightened out on the same line. In two 

 specimeus of D. nuttallii which have the head bent in the same way as in the supposed hybrid, the 

 width (lengthwise) of the red patch is 1.00 and 1.10 respectively. 



