CHRYSANTHEMUM MIDGE. 3 
Galls: They occur, three or four in number, at the extremity of the upper and lower 
surfaces of the stem of the Chrysanthemum atratum Jacq., which is irregularly rounded, 
varying in size from a large hemp seed to a large pea. Outside naked, consisting of a 
fleshy homogeneous massin which occur small, elongated cells or chambers each being 
inhabited by a larva. 
Distribution: On Raxalpa about 5,000 feet above sea -evel. (IE. Berroyer.) 
From this date, until it was first reported by Felt in the United 
States, frequent references are found in literature relating to its occur- 
rence and synonymy. Among these may be listed the following: 
Riibsaamen (4, p. 375), Kieffer (5, p. 21), (6), (7, p. 351, 353), (13), 
Baldrati (8, p. 40-41), Kertész (9, p. 69), Houard (11), and Kiister 
(12, p. 77, 274). 
On March 26, 1915, R. H. Pettit of the Michigan Agricultural Col- 
lege had his attention called to the existence of an infestation occur- 
ring in large chrysanthemum houses at Adrian, Mich. Specimens were 
submitted to E. P. 
Felt (14), State ento- 
mologist of New York, 
who in April of that 
year determined it as 
the chrysanthemum 
midge, Diarthronom- 
yia hypogaea (F. Low). 
In 1916 A. Gibson (21) 
reported the occur- 
rence of the midge at 
Ottawa, Canada. 
S 15 1 & Fic. 1.—Map showing distribution of the chrysanthemum midge 
ubsequently, reports in the United States and Canada. 
of its occurrence have 
been received from widely separated points, both in the United States 
and Canada. According to California florists, this pest has been 
present in that State for about 15 years. 
DISTRIBUTION IN THE UNITED STATES AND CANADA. 
To date, the midge has been reported from California, Connecticut, 
Delaware, the District of Columbia, Georgia, Illinois, Indiana, Maine, 
Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, 
New Jersey, New York, Ohio, Oregon, Pennsylvania, Rhode Island, 
South Dakota, Tennessee, and Virginia, as well as from Ottawa and 
Victoria, in Canada. 
Since the first records of its occurrence and seriousness were report- 
ed from the Middle West it would appear that the distribution of 
infested plants from this region was the source of its further spread 
to the other sections of the United States and Canada. | 
Its distribution, as indicated on the accompanying map (fig.1), is 
almost wholly confined to the larger chrysanthemum-growing regions 
of the United States, which include the areas surrounding the Great 
