348 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 10 



r 



Fxiller's 



Earth 



Series 



No. 4. Burn about same as on June 11, while probably too pronounced 



for general spray work, is not really serious. 

 No. 5. Slightly more than on 11th, but not really bad. 

 No. 6. O. K., burn comparatively slight. 

 No. 7. Burnt to a crisp. 

 No. 8. Burnt to a crisp. 



Conclusions 



Under field conditions lamp black is not practical, the black color 

 probably absorbs heat and increases the burn. That the presence of 

 an adsorbant has possibilities is clearly shown in a comparative study 

 of the burn between Nos. 5 and 7, and between Nos. 6 and 8. Nos. 

 5 and 6, having fuller's earth as an adsorbent, giving comparatively 

 little burn. Nos. 7 and 8, with the same dilution of arsenic, but with- 

 out an adsorbent, burned all the foliage absolutely to a crisp. Con- 

 clusions based on one season's observations, both as to toxicity for 

 insects and as to amount of burn indicate that there are possibilities 

 in the use of adsorbents with arsenic and further trials are planned on 

 a larger scale for the coming season. Estimates based on insufficient 

 data would indicate that if such a material may be used commer- 

 cially it will reduce the cost of arsenical sprays about two-fifths. 



Meeting adjourned until 2 p. m. the following day. 



Meeting called to order by Chairman A. W. Morrill at 2 p. m., Fri- 

 day, April 6, 1917. 



Chairman A. W. Morrill: The first on the program is a sympo- 

 sium on mail shipments of plants and plant products. This will be 

 opened by myself and then a general discussion will follow. 



Chairman Morrill: I have long held the view that postal ship- 

 ments are proportionally more dangerous as regards the transmission 

 of all plant pests than shipments by express or freight. The results of 

 the first year's experience of parcel post shipments in Arizona tend to 

 confirm this view. Altogether we inspected 543 of these shipments 

 and found that 4.4 per cent contained infested or diseased plants. 

 During the same period 2,432 freight and express shipments of plants 

 were inspected with the result that only 2.5 per cent were found to 

 contain infested or diseased plants. The pests found in parcel post 

 shipments were fully as important on the average as the pests found 

 in freight and express shipments. During the nine months' inspection 

 of parcel post shipments the following pests were found by our in- 

 spectors: Soft brown scale {Coccus hesperidum) 1 shipment; purple 

 scale {Lepidosaphes heckii) 1 shipment; rose scale {Aulacaspis rosae) 

 1 shipment; undetermined scales (immature) 3 shipments; plant lice 



