2 BULLETIN 833, U. S. DEPARTMENT OF AGRICULTURE. 
twelfth of an inch. When the leaf is affected, the galls usually occur 
on the upper surface. In such cases a slight swelling often may be 
observed on the opposite or under side of the leaf. Growth and 
development of both larva and pupa take place within this gall. 
When the pupa is fully developed it pushes itself out of the gall, still 
inclosed in the pupal skin. The latter then splits down the middle 
of the head and back to allow the adult to emerge. (See Pl. I, C.) 
In the adult stage the midge is a fragile two-winged fly, one- 
fourteenth inch in length. The abdomen of the male is yellowish 
orange, while that of the female is reddish orange. The adult on 
emerging leaves its pupal skin protruding from the opening of the 
empty gall. (See Pl. If, A.) As shown in the life-history studies, 
the adults emerge after midnight and egg-laying takes place early 
in the morning. 
HISTORICAL. 
In 1870, E. Perris (1, p. 177)! is recorded as having observed ceci- 
domyiid larve on Leucanthemum vulgare. Six years later J. E. Von 
Bergenstamm and P. Léw (2) also recorded larvee which in all prob- 
ability were cecidomyiid, as they were found attacking the young 
leaves of Chrysanthemum leucanthemum (Leucanthemum vulgare.) In 
August, 1875, E. Berroyer collected specimens in Raxalpa, a group of 
the Eastern Alps of Austria-Hungary, at an elevation of 5,000 feet _ 
above sea level. These specimens, which consisted of subterranean 
galls, and two adult male midges, were submitted to Franz Léw (8) 
by Von Bergenstamm. Franz Low made the original description in 
1885, which freely translated is as follows: 
Male: Antenne 2-14 jointed. Peduncle shorter than the segments. Terminal 
segment with two whorls of stout sete. Wings cloudy white. All veins, also costal 
vein white. Second parallel vein straight, disappearing in the apex of the wings. 
First branch of the third parallel vein so weak that it is not visible, unless under best 
of light and high power, but the wing fold on the other hand is very plainly discernible. 
Halteres white. Legs with closely adhering hairs, also appearing white. 
Larva: The still unknown larva causes galls on the underground parts of the stem of 
Chrysanthemum atratum Jacq., in which their complete transformation takes place. 
In each are also found several larve, each larva occupying one cell for itself. 
Pupa: The pupa has (like the pupa of the Asphondylia species) three pairs of horns, 
but on the other hand, lacks the rows of delicate horns found on the dorsal surface of 
abdominal segments of the Asphondylia species. 
The two cephalic horns are very large, widely separated, slender, quite pointed and 
with the point somewhat recurved. The horns of both other pairs are very small, 
alike in size and structure, pointed and also with the point somewhat recurved. They 
occur in such a manner that a horn is located above and below each eye of the pupa; 
consequently, the horns of one pair are widely separated from each other. In the cells 
of the galls in which pupation of the larva takes place, the pupe are so situated that the 
head points to the periphery of the gall. 
1 Numbers in parentheses refer to “ Literature cited,’’ p. 23. 
