Sg Saget, Sean, Siar Nee ce eee 
* in r x 7 ~~ aS . 
=! Re Ce a . <— 
= Fs S - 4 
; 28 
A pair of black pits at base of last segment, which is ovate ‘ 
COoniG’ And, POInteds Aeon S etek Sik kaos .Agriotes. 
Cerci present......Athous, Corymbites, Asaphes, Cryptohypnus. 
We have recognized five or six species of Melanotus larvae, two of © 
which are definitely identified, and may be separated by the following — 
key. Both have the body very finely ‘and sparsely punctate, and the — 
last segment finely tuberculate. % 
Last segment finely, sparsely, and indistinctly punctate above, 5- 
dentate apically, striee of muscular impressions at middle of body — 
12-14, sometimes fewer in younger specimens (Pl. VL, Fig. — 
aE) Ee See TOE ee EC a eae: .. communis. 
Last segment distinctly and rather coarsely punctate above, trian-_ 
gulate or feebly tridentate apically, striae of muscular impressions 
at middle of body 4-5, rarely fewer (Pl. VI. Fig. 6, 7, 8) cribulosus. — 
A larval skin like that of cribulosus, but with the apical teeth more — 
narrow and prominent, especially the median one, was found in a pupal — 
cell with a fine male I. americanus. Another species frequently found — 
in rotten wood, has the surface strongly punctate. 
a 
CARDIOPHORUS sp. 4 
- 
(Plate IV., Fig. 6.) : 
A very peculiar long and slender elaterid larva, quite unlike a wire- 
worm in general appearance, although belonging to the same ‘ome 
and doing ‘the same mischief in the corn field, was found by me in 1886 — 
mining and perforating the roots of corn in the sandy soil along the — 
Mississippi in Alexander county, Illinois, with the effect to greatly delay — % 
the growth and permanently dwarf the corn. Although known only as” 
a root insect, it probably attacks the kernel earlier, and its description 
is given here with that of other members of its family. It may be distin- 
ewished at once from any other larva likely to occur in the same situa-— . ; 
tion by its very long and slender form, and by its nodulated appearance, re 
due to the expansion of a part of each segment. Pn 
It is evidently capable of very serious injury to corn, channeling 
and burrowing the roots in every direction, and often causing decay—_ 
much more serious than the immediate mechanical injury of their min- _ 
ing. The perforations through the surface of the root were in some 
instances so numerous and close as practically to deprive the plant of all 
use of its roots. a 
The number of larve found in a hill varied from one or two to ten — 
or twelve, and their great activity in the ground—through which they 
moved with ease—suggested the probability of their going from hill to , 
hill, as their necessities required. This genus has never been reported: 
in the larval state in this country except on the occasion mentioned, and — 
then on no other plant except corn. Search among the roots of other 
plants in the infested field—pigweed (Amarantus), purslane, pigeon- — 
grass, cocklebur, ete..—failed to discover them. y . 
Description—It is nearly an inch long when full grown, and scarce- ie 
ly a millimeter (.04 inch) wide, whitish in color, becoming yellowish 
e 
a 
