No. 6. DEPARTMENT OF AGRICULTURE. 161 



When such specimens are properly prepared, labeled and exhibited 

 they will not only help the teachers a great deal in Nature study, 

 but also will be of vast economic importance in showiug to pupils 

 larmers and orchardlsts which are their friends and which their foes, 

 and in throwing light on essential points in the knowledge of their 

 life history, which must be recognized in the work of practical insect 

 warfare to save our crops from annual loss of over a million dollars, 

 which I fully believe is not too high an estimate to place upon the 

 annual damage of insect pests to cultivated crops alone in this 

 State. 



Whenever insects occur in devastating numbers we aim to collect 

 specimens of them and their work, provided we do not have them 

 already represented in the collection. We also make a study of their 

 natural enemies and the various plants upon which they feed. As 

 the duplicates are preserved in good condition they can be used in the 

 school collections or in exchanges. 



We have not yet developed a system of making exchanges, but the 

 time is at hand when it is worth while to undertake this work and 

 attempt to make the collection as complete as possible in those 

 species occurring in Pennsylvania or liable to come into this State. 



During the year 1911 there were 1,090 accessions of specimens 

 added to our catalog pertaining entirely to zoology; also, much 

 material was received (not pertaining to zoology) from as many more 

 contributors, that were not given any accession numbers. Some of 

 these numbered accessions include insects and other material, such as 

 birds, reptiles, etc. 



The number of accessions may not be as large as during previous 

 years, but the material collected by the office employees on their own 

 time was placed under one accession number for the entire year. 



Total number of accessions, 1,090 



Number pertaining to insects, 1,026 



Number pertaining to invertebrates other than insects, 73 



Number pertaining to fishes and reptiles, 15 



Number pertaining to birds, 8 



Number pertaining to mammals, 3 



BREEDING CAGES 



Whenever we have collected or received specimens of living insects, 

 the life history of which is not fully known, or which are in their 

 immature stages, and hence not to be determined, we have kept them 

 enclosed in glass and cloth covered vessels, commonly called ''breed- 

 ing cages," for the purposes of making a careful study of them in 

 every detail, and also procuring specimens in their various stages 

 of transformation. 



Often the only good specimens obtainable by the collector are to 

 be had by the one method of rearing them to maturity in breeding 

 cages. Thus it becomes important to keep these cages and study the 

 transformations of the pests. The dates for practical remedies often 

 depend very decidedly upon the exact dates of the transformati<^n of 

 the insects. For example, there is no satisfactory remedy for the 

 Lecaniiim Turtle-shell, scale of peach and plum excepting to ^\atch 

 for it at the time of its hatching, and then apply a comparatively 



11_6__1911 



