DIVISION OF ENTOMOLOGY. 147 



1000 by an agent of the Division, and the results will be published in 

 Bulletin No. 30 (new series). As a result, probably mainly of the 

 work done, but undoubtedlj'^ also of the work of natural enemies and 

 changed weather conditions, no complaint has been made the present 

 summer of the work of grasshoppers in this locality. Other specific 

 work of this character, but of less importance, has been carried on in 

 many directions, and will probably achieve results worthy of special 

 mention at a later date. 



(b) EXPERIMENTAL WORK VV^ITH REMEDIES. 



The work outlined in the last report has been continued. Many 

 substances have been experimented with. A number of disputed 

 claims as to insecticidal values have been set at rest. The lime, sul- 

 phur, and salt wash, so successfully used in California against scale 

 insects on deciduous trees, but which had previously been found 

 unsuccessful in the East, has been again experimented with under 

 different conditions, and has been found to be very successful wher- 

 ever the weather conditions hapi^ened to be ver}^ favorable, duplicat- 

 ing in a measure the conditions on the Pacific coast. The general sub- 

 ject of insecticidal measures, after extensive experimentation, has 

 been covered in Farmers' Bulletin No. 127, issued February 6, 1901, 

 and for which there has been great call from agriculturists and horti- 

 culturists. It is a detailed treatise of the more imj)ortant insecticides, 

 with directions for their preparation and use. The results of a large 

 series of experimental tests will be published in Bulletin No. 30 (new 

 series) of the Division. 



Experimental work with fumigants has also been carried on, and 

 some important experiments have been made in the way of fumi- 

 gating bake shops and granaries against grain insects, and tobacco 

 establishments against the tobacco beetle, or "cigarette beetle," as it 

 is sometimes called. A lengthy series of insecticidal operations was 

 carried on by the first assistant in southern California, which were 

 reported upon in the Yearbook of the Department for 1900. 



(c) DETERMINATION OP SPECIMENS SENT IN. 



As reported in previous years, the different experts in the Division 

 have been obliged to devote much of their time to the naming of 

 specimens for experiment station entomologists and others who have 

 not access to large collections, either of specimens or of books. The 

 fact that the Division is obliged to name specimens for entomologists 

 of the experiment stations is by no means derogatory to these station 

 officials, since the field of entomologj^ is so great that one man can 

 hardly have expert knowledge of the highest character of more than 

 one of the large number of groups of insects. The office force of the 

 Division, however, is composed of a number of such experts, and 

 entomologists working single-handed are practically obliged to con- 

 salt them. This work, as has previously been pointed out, altliough 

 excessive, makes no showing in the practical output of the Division. 

 It is indirectly, however, of much practical value as facilitating the 

 work of station entomologists. 



(d) GENERAL INVESTIGATIONS OF THE LIFE HISTORIES OF INJURIOUS 



INSECTS. 



During the fiscal year life-history notes were made upon 154 species 

 of insects which had not before been studied in the insectary. The 

 catalogue number of the biological series so studied reached 9,441 on 



