62 BULLETIlSr 351, U. S. DEPAKTMEXT OF AGKICULTUEE. 



The females during the spring development are sometimes heavily 

 attacked by hymenopterous parasites, especially species of the genus 

 Coccophagus. At the start of reproduction the larvae of the cocci- 

 nellid Hyperaspis hinotata Say (fig. 17) enter the brood chambers and 

 attack the lecanium larvae, while later the maturing larvae of this 

 beetle, in attempting to enter the brood chambers, dislodge many of 

 the gravid females, thus destroying at once both the female and the 

 unborn young. (See fig. 18.) 



Cold, wet weather at the time of reproduction causes many larvae 

 to die in the brood chamber. These frequently clog the exit and pre- 

 vent the egress of the remainder of the brood. This condition was 

 especially noticeable in the season of 1912, when owing to protracted 

 rain 5 per cent of the gravid scales were affected in this way. 



During the leafward migration most of the young succeed in reach- 

 ing the leaves, and the loss at this period is due mainly to drowning 

 by sudden rains and to the dropping of larvae from dead twigs. Dur- 

 ing the leaf phase the larvae are often heavily attacked by predatory 

 enemies, but the female larvae are practically free from parasitic 

 attack, and the males are but shghtly attacked. However, after 

 returning to the twigs the females are subject, at times, to a heavy 

 parasitic attack which may cause a mortahty as high as 20 per cent. 

 They are also subject to attack at this time by a pyrahd moth, 

 Laetilia coccidivora Comst. In conclusion it may be said that the 

 mortaihty from weather conditions throughout the year is not more 

 than 50 per cent, and that in favorable seasons it is almost neghgible. 



ATTENDANTS. 



The terrapin scale excretes a honeydew which is very attractive to 

 ants, and during the time in w^hich it is being deposited all the species 

 of ants in the vicinity will be found working upon it, while at other 

 seasons no ants will be about. In the early spring, when the fruit 

 buds are about to burst into bloom, considerable honeydew is excreted 

 and ants are then actively working, but during the period of re- 

 production very few ants appear. When, however, the twigward 

 migration of the females starts, the ants return and remain in almost 

 constant attendance mitil the scale hibernates. There is no species 

 of ant that habitually attends this scale, but most of the orchard 

 ants feast upon its bounties. Only slight benefit to the scale results 

 from the attendance of the ants. Some of them are pugnacious and 

 undoubtedly tend to ward off predators and to frighten away and 

 confuse parasites. 



The following four species taken at Mont Alto, Pa., attending this 

 scale were identified by Dr. W. M. Wheeler: 



Formica trundcola Nyl. subsp. Integra Nyl. 

 Formica fusca L. var. subsericea Say. 

 Lasiiis niger L. var. americanus Emery. 

 Prenolepis imparis Say. 



