383 



the name of Scaptomyza by the English entomologist, Hardy; but the 

 best authorities on this subject accord it only subgeueric rank. 



Although no experiments have as yet been made in this direction, 

 so far as we can learn, still there is a i^ossibility that the attacks 

 of this insect may be prevented by sprinkling the plants with Paris 

 green and water, at the rate of 1 pound of the j)oison in 200 gallons 

 of water, first mixing the former with an equal quantity of freshly 

 slaked lime, adding water to the mixture, and allowing it to stand for 

 several hours before using. The addition of the lime is for the purpose 

 of rendering the poison harmless to the plants. It will, of course, be 

 advisable to make the application before the plants have been attacked ; 



Fig. 41. — Trypeta fratrla: a, larva; /, adult — enhirgeil ; c, d, e, anterior and posterior extremities 

 of larva — still more enlarged (original). 



after once the larvai have made their way to the interior of the leaves 

 it will be difficult to reach them by means of any external application, 

 although there is a possibility that even then a penetrating liqnid like 

 the kerosene emulsion might find its way to them and accomplish their 

 destruction. 



THE PARSNIP LEAF MINER. 



So little attention has been given in the past to a study of the life 

 histories of our Diptera that the early stages of only a very limited 

 numoer are at present known. An extended search through the pub- 

 lished records has failed to bring to light a single fact bearing upon the 



