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tender leaves and ate rapidly away to the midrib, sometimes consuming 
this also. The foliage of the bean and cowpea they perforate with 
large, rounded holes. When very abundant, the beetles strip the leaves 
to their veins and midribs. The beetles themselves would seldom 
attract attention, as they feed and rest during the greater portion of 
the day almost exclusively on the under side of the leaves. On wild 
‘plants, on the contrary, the beetles are often to be seen on the upper 
surface near the tops. Injury to the foliage of beans is most notice- 
able, when observed late in the season, on the lower leaves. 
The only other leaf-feeders that have been observed about the neigh- 
borhood of the District, that are at all likely to be mistaken for this 
species by the nature of their work, are the grape-vine Colaspis (Colaspis 
brunnea) and the twelve-spotted cucumber beetle. The latter, however, 
works in a much different manner. On beans and soja beans it was 
observed feeding on the upper surface of the leaves, but the holes that 
it makes are very small and irregular and searcely likely to be mistaken 
for those of Cerctoma, except perhaps a long time after they have been 
eaten out. 
The beetles are rather sluggish and seldom seen in flight, nor are 
they easily disturbed, and hence may be readily captured by hand. 
When alarmed they drop to the ground, but soon reascend to the plant. 
LIFE HISTORY. 
The life history of the species, it is superfluous to remark, is not yet 
very fully known. Undoubtedly it passes the winter in the adult con- 
dition. I’ew exceptions to this rule are known in the Chrysomelidz. 
As might readily be surmised from its known distribution, it exhibits 
considerable variation in the periods of appearance. In the Gulf States 
the hibernated beetles appear as early as April, Mr. Webster having 
sent specimens to this office collected at least in the second week in the 
mouth; in Shawnee County, Kans., it was also observed in April; in Gib- 
son County, Ind., and in Shenandoah County, Va., it was observed 
June 22 and 26, respectively; while at Ithaca, N. Y., the writer collected 
the beetles no earlier than July 6. In the vicinity of the District of 
Columbia thes pecies has been noticed as early as the middle of May 
and as late as the fourth week of August. A larva and a pupa, evi- 
dently stragglers, were collected as late as September 4, but no beetles 
could be found at this time. 
The eggs are laid around the stem just below the surface and in clus- 
ters, according to Mr. H. E. Weed, of from six to ten, and the larve 
eat around and within the stem. In Mississippi he has further stated 
that there are two generations a season, which overlap, however, so that 
the beetles are to be found at most any season, though they are more 
abundant in April and July. The first generation is said to be pro- 
duced upon garden beans and the second upon cowpeas, and the habit: 
of the mature insects of e iting holes in the leaves is especially notice- 
