8 BULLETIN 535, U. S. DEPARTMENT OF AGRICULTURE. 
of the species. In 1900 A. B. Wolcott (5) made mention of the cap- 
ture of the beetle at Bloomington, Ill. Injury by this species was 
briefly mentioned by J. J. Davis in Illinois in 1910 (6). In 1910 also, 
Blatchley (7) recorded its occurrence in Lake County, Ind., anc in 
1911 A. F. Winn (8) observed it at Westmount, Quebec, Canada, on 
horse-radish received from Montreal. It is not stated, however, 
whether the insect was believed to come from Montreal or from 
Westmount. In Europe brief notes were published by Heikertinger 
in 1911 and 1912 (9, 10). 
FOOD PLANTS. 
This beetle is partial to horse-radish and marsh cress. It was taken 
once on young cabbage in hotbeds in early spring by the junior author 
but was not observed to be eating. The future no doubt will reveal the 
possibility at least of other host plants. 
SEASONAL HISTORY. 
THE EGG. 
The eggs are deposited from the latter part of April or early May 
through spring and summer until early August. The manner of 
placing and the position are variable, but the preferred location is on 
the tender petioles of young leaves, in the crevices where they leave 
the root. A few eggs have been found on the ground and on different 
places on the leaves, above and below the ground, and also carefully 
placed in the pits made in the stems and petioles by the larve or 
adults. They usually occur in small masses, either carefully arranged 
side by side in single rows, or two rows high, or carelessly piled with- 
out order. Occasionally an egg is found standing on end. The 
attachment to the plant is not very secure and often an egg-mass falls 
on the slightest disturbance. In the cages from 2 to 26 eggs were 
laid at intervals by a single female. While the most frequent number 
of eggs deposited was 22, at times 44 were deposited, indicating that 
about 22 eggs are developed in the ovarian tubes at one time. Copula- 
tion often takes place between deposition of batches of eggs, but it 
has not been determined whether or not this:is necessary before the 
deposition of each batch. Judging from analogy, however, it may 
not be necessary. Hundreds of eggs were obtained in the insectary, 
but the egg record of one gravid female (Table 1) will suffice to show 
the egg-laying capabilities of the species. This female was placed 
in a vial with a portion of horse-radish leaf May 1, 1915, and the 
total number of eggs laid was 418. | 
\ 
