234 Leaf-Miner. [ZOE 
foliage mentioned as the food of the grouse, but they probably eat 
leaves of clover early in summer, just as valley quail do in win- 
ter. The juveniles eat a great many ants. 
‘Some seasons, when there are no berries and very few seeds, 
they live almost entirely upon the bulb of a species of grass, ap- 
_ parently Melica bulbosa, which grows at the head of springs and 
rivulets. The birds get the bulb by scratching. Such seasons they 
start for the foothills sooner than when food is abundant. 
ON A LEAF-MINER OF POPULUS FREMONTI. — 
BY C. H. TYLER TOWNSEND. 
Almost every spring the cottonwoods in the town of Las Cruces, 
New Mexico, and its vicinity, are badly infested with a leaf-miner, 
which up to the present time has baffled all attempts at breeding. 
The cottonwood is our only native shade tree in the Mesilla Valley, 
there being only the one species, Populus fremonti; and as this in- 
sect has proven a serious pest to it, the following notes on the larva 
will probably be of interest, although the imago is unknown. A 
very brief notice of this miner was published in Insect Life, vol. 4, 
pp. 26-27. 
_ It was found on April 30, 1891, that nearly every tree in the valley 
was most thoroughly infested, the majority of trees having almost 
every leaf mined out and blistered. The larvz eat out the entire 
inner portion or parenchyma of the leaf, leaving the two skins 
whitened and inflated like blisters. They entirely and irrecoverably 
ruin the foliage of the tree, giving it a most desolate and dying ap- 
pearance. The trees, however, gradually put forth a new set of 
leaves, and though they apparently soon recover their normal healthy 
appearance it is clearly evident that this process must be a great tax 
_ on their vitality. I have even been told that in some previous years 
the second crop of leaves has been likewise destroyed, but I cannot 
vouch for the accuracy of this statement. On the above date the 
larvee were of several sizes, the largest being about seven-sixteenths 
_ of an inch in length. In general color they are nearly white, with 
_ same black dots on the anterior segments below and on the seg- 
: ‘ments next the head above. Two larve were often found in one 
rs . _ leaf, their mines beginning in separate parts of the leaf and gradually — 
_ approaching until they coalesced. 7 | 
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