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INSECTS INJURIOUS TO THE PINE. 167 
row extending lengthwise of the tree or limb, from six to twelve inches 
in length, but it is less straight in this species, being usually curved 
more or less, and according to accounts it is often perfectly zigzag. The 
same notches are formed along its sides as noticed in the foregoing 
species, in which the eggs are deposited ; but the lateral burrows which 
branch from the central one have no regularity whatever to them, being 
given off sometimes obliquely and sometimes at right angles, sometimes 
abruptly widening into a broad irregular, flat cavity, and sometimes 
continuing of the same width through their whole length, either straight, 
irregularly wavy or tortuous, turning here and there, wherever an unoc- 
cupied space occurs into which they can be extended. These branches 
are usually of the same width with the central gallery, and like it are 
furrowed equally deep in the outer sur- 
face of the wood and the inner surface 
of the bark. The pupa state is passed in 
a cell excavated in the bark, and not in 
the wood, as in the foregoing species, and 
when changed into a beetle this cell is 
extended onwards through the bark for 
the escape of the insect. Being a larger 
species than the preceding, the galleries 
which it excavates, and the holes it per- 
forates through the bark, are proportion- 
ally larger. Several dead individuals 
may usually be found in the galleries of 
this as of the other species. (F itch.) 
I have found the “mines” or galleries 
of this bark-borer under the bark of the 
southern pitch pine at Houston, Tex., 
where it seemed to be abundant. Beetles 
taken from the mines were sent to Dr. G. 
H. Horn, who kindly identified them as 
T. calligraphus. Fig. 74 represents a ¢ 
typical mine. It consists of a primary or ® 
main gallery or mine which is 33™™ wide; 
the holes for the exit of the beetle, of 
which two are represented in the engrayv- Fic. 74.—Mine of Tomicus calligraphus 
F 7 é 3 in southern pitch pine, Houston, Tex. 
ing, being 2™ in diameter. The primary Packard del. 
gallery is nearly straight, with, in the cases noticed by us, only one set 
of secondary galleries arising on one side, as represented in the figure. 
The secondary galleries are from one to nearly two inches in length, and 
at the end a little over half as wide as the main gallery. At one end the 
main gallery opens into a broad irregular cell, where the worm probably 
transforms into the pupa, connecting with the hole for the exit of the 
beetle. 
Another form of cell without any lateral or secondary galleries is 
