No. 6. DEPARTMENT OF AGRICULTURE. 131 



universally approved by the scientists and most of the practical men 

 of the country. 



Our investigations of the Oyster-shell Scale and the Scurfy Scale 

 have given us the full life histories of these pests in this State, 

 showing that they have two broods per year, one appearing about th'^ 

 middle of May and the other about the first of August or sometimes 

 earlier, and as these are dates when the young free-moving pests 

 are crawling about and are very delicate, they are consequently the 

 periods when spraying for these pests will be most effective, since 

 spraying for them in the winter when they are in the egg stage and 

 better protected has not proven as satisfactory as for the San Jose 

 Scale at the same time. We have had fair success with the lime- 

 sulphur-salt wash in early spring for Scurfy Scale, but not for the; 

 ( )yster-shell. 



Our studies of the food of birds have been continued, and we are 

 at this time working on the food of blackbirds and crows, having 

 much proof that the latter feed on insects all year, even during the 

 winter months. We have found in their stomachs such injurious 

 insects as the Red-legged Grasshopper, the Clover-leaf Weevils and 

 other pests. Our investigations of the food of Batrachians, or frogs, 

 toads and salamanders have proven the great value of these 

 creatures as insect destroyers, and also that they do not eat many 

 beneficial insects and do not have any obnoxious habits in destroying 

 the property of mankind or in any other way. A Bulletin on these 

 lowly forms of Vertebrate Animals is in course of preparation and 

 will be issued during the coming year. 



Considerable attention has been given to the Reptiles of Penn 

 sylvania. Collections have been made as far as time will permit, 

 and the food of these reptiles has been carefully studied. This has 

 resulted in new knowledge concerning many of them, and has proven 

 that the Garter Snake, which was supposed to be mostly insectiv- 

 orous and consequently very valuable about the premises, feeds to 

 a great extent upon toads and frogs, and as these amphibians are 

 among the most valuable of insect destroyers of the farm, the Garter 

 Snake becomes obnoxious and objectionable in its economic aspect. 

 On the other hand the two forms of Blacksnakes, known as the 

 Blue Racer and Pilot, are proven to feed during the early part of the 

 summer upon birds' eggs and young birds, and thus are objections 

 ble, while from the middle of the summer until the hibernating 

 season they feed mostly on rodents, such as rats and mice, and 

 thus become very beneficial in their economic relations to mankind. 

 Several snakes, such as the Hognosed Adder or Spreading Adder, 

 Blowing Viper, Copperheads and Rattlesnakes, feed to a great ex 

 tent upon large caterpillars, and where these insects occur upon 

 the ground they are certainly held in check by such serpents. Were 

 it not for the poisonous effects of the Rattlesnakes and Copperheads 

 they could well be protected on aecounut of their beneficial feeding 

 habits. A Bulletin on this subject is in the course of preparation 

 and will be issued soon. 



We have investigated the habits of the Canker Worms that have 

 been so destructive during the past two years in the central and 

 western portions of our State, and have published that they are the 

 Spring Canker Worms (Paleacrita vernata). of which the females 

 climb the trees early in the spring, generally in the latter part of 



