Deformity of Maxilla in the House Sparrow. — The accompanying illus- 
trations show the overgrowth of maxilla after loss of mandible in a male 
Passer domesticus. The photograph was taken by Mr. A. H. Verrill, who 
shot the bird in his yard in New Haven, December io, 1900, and brought it 
to me in the flesh. 
The culmen measures .60 inch from nostril against an average of .39 
inch in five normal males of this species. The maxilla measures .16 inch 
in depth at tip on the right side, but had been worn off on the left where 
all that was left of the mandible approached it. The normal outer cov- 
ering of the bill persists at the base in the form of a triangle, the apex ex- 
tending .31 inch along the culmen; this portion thus showing much the 
shape of a normal maxilla. On the rest this outer layer has disappeared, 
doubtless from effort of the bird to scoop up food. Mr. Verrill said he 
saw it attempt to pick up pieces of cracker in this manner. 
Of the mandible onlj' a fragment .28 inch long (measured from the com- 
missural angle) at the base of the left ramus is present, the rest having 
been lost through some accident. The wound had healed, leaving the 
tongue exposed. Most of the feathers on the upper throat and malar re- 
gion have been worn away, and the plumage in general was dirty, rum- 
pled and matted, as the bird was of course unable to preen. The body was 
emaciated, but there was a little subcutaneous fat, and a partial molt was 
in progress. _ The stomach contained a little white sand, and a soft, whit- 
ish substance, probably cracker. 
That this bird in its crippled condition after the loss of the mandible 
succeeded in living the time necessary for the great overgrowth of the 
maxilla seems to me very remarkable. Mr. W. H. Hoyt of Stamford has 
shown me a mounted Parrot ( Amazona leucocephala ) in which the mandible 
had grown over the maxilla and extends for more than one third of an inch 
upwards, but this bird lived in captivity. — Louis B. Bishop, M. D., Ne-w 
Haven , Conn. Auk, XVIII, April., 1901, pp./f5'~6. 
/Zi 
