
is 
vod, I, No. 6, | September 1, 1913. 
METHODS OF STUDYING LACHNOSTERNA. 
By J. J. Davis. 
Owing to the large number of species contained in the 
genus Lachnosterna it is essential, for completeness, that 
Studies be made in various parts of the United States, pri- 
Marily to determine the length of the life cycle and, al- 
BO, which species are economically most important. DBDoubt- 
less the larvae of all species feed on the roots of living 
vegetation, but it is not known just which ones attack eul- 
tivated plants. Secondarily, to secure other details of 
the life history and habits, especially of the food habits 
of the beetles, time of appearance of those economically 
important in a given locality, periodicity of abundance, 
fee &l1l of which may be of value in devising means of con- 
rol. 
; These notes are given in order that others of this di- 
vision may become acquainted with our desires, know what 
methods have been found most satisfactory, and use the in- 
formation should opportunity arise. We should like to learn 
of all contemplated Lachnosterna projects in order that 
special directions may be given to suit the locality. 
The cages to be used may be either 12, 15, or 16 inch 
standard flowerpots, preferably 15 or 16 inch size, or wire 
screen cylinder cages. In using flowerpots care must be 
taken to keep the soil well watered, otherwise the soil will 
bake and the grubs be killed. As winter approaches, the wire 
cloth tops of such cages are removed and the tops of the 
ots covered with a straw and manure mulch. In the Southern 
states such a protection will probably not be required. 
Several styles of wire-screen cages are available. 
These are cylinjrical in shape and measure 20 inches in diam- 
eter and $0 inches in depth, with a cone-shaped cover to fit intc 
the top of the cage. Probably the best type is made of 6-mesh 
#20 galvanized wire, covered on the inside with 18-mesh pearl 
(galvanized) wire cloth, Should the lighter pearl wire rust 
out before the beetles mature (supposedly in three years) the 
grubs will at least have become sufficiently large to make 
it impossible for them to escape through the 6-mesh screen, 
which is heavy and quite durable. A cage of the pearl wire 
cloth without the outer heavy wire screen may be used for 
studying the life cycle of the more southern species, which 
probably do not have a life cycle greater than two years; for 
such a cage will last at least two seasons. The cone-shaped 
tops of these cages are made of pearl wire cloth with suitable 
supports, with a basal band of galvanized iron to fit snugly 
into the top of the cage. The double wire cage, including top, 
cOsts about $6; the single wire cage, suitable for work in 
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