404 NEW YORK STATE MUSEUM 



grayish on the outer margin, a dot near the middle, a spot near 

 each angle and several longitudinal streaks along the hind mar- 

 gin, all dark brown. The female deposits her eggs in clusters on 

 the underside of leaves during the month of July; they hatch 

 shortly, and the young caterpillars at first consume only the under 

 surface of the leaf, leaving the upper unbroken, but as they in- 

 crease in size the entire leaf is devoured. These interesting cater- 

 pillars are social in habit, remaining in rather compact groups 

 when not feeding, and attain maturity in this latitude during 

 August or early September. Their gregarious habit frequently 

 results in one or more branches being entirely stripped. This species 

 has but one brood in the North but in the South there are said to 

 be two generations. It is seldom abundant and while displaying 

 a marked preference for apple, also occurs on plum, cherry, rose, 

 thorn and pear. Like other leaf-feeding species, this pest can 

 be easily controlled by thorough spraying with an arsenical poison 

 such as paris green, london purple or arsenate of lead, and in or- 

 chards where spraying is the rule, it very rarely causes trouble, 

 particularly if the more adhesive arsenate of lead is employed. 



Fall apple leaf miners. There are several species of small leaf 

 miners which affect apple foliage in the fall, one of which makes 

 a rather elongated mine on the under surface of the leaf, eating 

 out the soft tissues completely, so that the upper surface presents 

 a honeycombed or spotted appearance due to the veins and vein- 

 lets which are thicker than the upper epidermis. This species is 

 found on appletrees during September and even in October and 

 as late as early November. It has been termed the unspotted 

 tentiform miner of the apple and is designated scientifically as 

 Ornix geminatella Pack. 



There is another leaf miner which works in apple foliage in a 

 very similar way and at the same time, which is known as the 

 spotted, tentiform miner, Lithocolletes blancar- 

 d e 1 1 a Fabr. The work of this insect may be distinguished 

 from the one mentioned above, by the spotted character of the 

 upper surface of the mine caused by the small larva eating a little 

 in one place and then moving to some other part of the mine to 

 eat a little in another. This species transforms to the pupa within 

 the mine, remaining there over winter, the moth emerging in the 

 spring, while the larva of Ornix geminatella pupates 

 in the edge of a turned up leaf, the adult appearing in the spring. 



Still another species, the trumpet miner, Tischeria 

 malifoliella Clem., occurs on apple leaves at this time, 



