130 THE MONTANA EXPERIMENT STATION 



above and the one below. The cone at this time is soft and the 

 scales are thick and fleshy. As the caterpillar grows more food is 

 required and the burrow is dug more deeply into the cone. The 

 seeds have formed by the time the caterpillars have hatched, but 

 they are not attacked until the caterpillars are about half grown. 

 Meantime the caterpillar has eaten its way inward until it is next 

 to the central shaft of the cone. Then the seeds are attacked and 

 tile larva works its way up and down the shaft often in a more or 

 less spiral course around the shaft. In almost all cases, all or practi- 

 cally all, of the seeds are eaten. If any are left it is generally at 

 the tip of the cone. The caterpillar nears maturity as the cone 

 hardens and most, if not all, of the feeding is done by the tim:e the 

 cone is fully hardened and opened for the escape of the seeds, 

 though a few caterpillars have been found in cones on the ground 

 in the fall. 



The adult larva is about three-fourths of an inch in length. The 

 general color is an opaque resinous red, making it inconspicuous 

 when crawiling over a cone. In general appearance and motions it 

 is much like the codling moth larva. 



The accompanying photographs show the work of the larvae 

 in the cones and seeds. 



A rather firm cocoon is constriicted in the more or less spiral, 

 tubular burrow, generally about midway between the end of the 

 cone, and in the cocoon the larva transforms to the pupa in the fall 

 of the year, and in this stage the winter is passed. In the fall and 

 early spring, as well as in the winter, wie have repeatedly found the 

 pupae in the cocoons. A close examination of the pupae in the fall 

 shows a large proportion of the cocoons to contain the larvae of 

 various parasitic Hymenoptera in, place of the host. Thus thisin- 

 • sect has one annual brood or life cycle in Montana. 



EXPLANATION OF PLATE. 



Figure a: A single egg on a bract, enlarged; b, moth, enlarged; 

 c and d, a cone broken open showing the work of the larvae; e, seeds, 

 showing how they are eaten by the larvae. 



