1910] Johnson—Diptera of New England 231 
Xylota (?) tuberans Williston. 
This interesting species has been collected at a number of places 
during the past few years: Squam Lake, N. H., June 22, 1907 
(Dr. G. M. Allen); Mt. Equinox, Manchester, Vt., June 5, 1910. 
Hypoderma bovis De Geer. 
The ox-bot seems to have been unusually prevalent the past 
season. Mr. Wm. Merrill of West Newbury, Mass., in a letter 
dated May 17, 1910, says: “I have never seen the ox-bot so 
numerous; of our eight head of cows every one is affected with 
from six to over sixty each. Other cows in the neighborhood are 
also affected.’’ I visited West Newbury, May 27, and saw the 
cows referred to but obtained only one larva; most of the larvee 
having already left the cattle. The larva was apparently full 
grown, but light brown in color. 
During the early part of June while at Manchester, Vt., I found 
the cattle slightly affected, about half of the cows having from 
one to four bots. Three larvee were obtained June 9, one of which 
was white, about half grown, I should judge, but the swelling 
was just as large due to the presence of a large amount of pus; 
the second specimen was a light brown apparently full grown, 
but like the one from West Newbury failed to pupate; the third 
was evidently ready to leave the cow, the opening was large and 
the larva blackish in color. It was placed in damp earth and 
pupated June 11, the imago emerging June 30. From these obser- 
vations I am inclined to doubt the statement that “‘the full-grown 
larva when escaping from the back is of a grayish-white color.” 
In comparing the above-mentioned fly with specimens of H. 
lineatum De Villiers, from Texas and Colorado, I find that the 
species is H. bovis, the occurrence of which in North America has 
been doubted. Whether all of the larve referred to belong to 
this species I cannot say, as both species probably occur in New 
England. H. bovis can be readily distinguished from H. lineatum 
by yellow pile of the thorax extending to the suture, the broader 
and less conspicuous polished ridges on the thorax, the wings 
slightly darker, the entirely black metanotum and black tibie. 
It is also noticeably larger and more robust. 
