23 
NOTES OF OBSERVATIONS 
PSILA ROSJE. 
Carrot Fly, larva and pupa natural size and magnified. 
9. Psila Rosse. Carrot Fly. The following observations give 
details of methods of treatment found most successful in pushing on 
healthy growth, with notes of the use of special applications, as wood- 
aslies, soot, gas-lime, soap-suds, &c., and also of the use of paraffin; 
attention is also drawn to the importance of keeping up an unchecked 
growth, and especially of the danger of attack from the Fly penetrating 
down into the ground to lay its eggs in the Carrots when disturbed by 
thinning. I endeavour to give the observations in such order as may 
place the notes referring to any special applications or methods of 
treatment together, and the first include details of application of 
paraffin. Mr. Alexander Anderson mentions that he has grown the 
early French Horn Carrot for the last four years at Oxenford Castle, 
Dalkeith, on a bed of tree-leaves covered with soil composed of the 
emptyings of flower-pots, boxes, &c., and consequently of a light 
friable texture. The size of the bed is fifty feet square, which is sub¬ 
divided into four feet beds, and is sown broadcast. The crops have proved 
clean and good, with the exception of last year (1879), when they were 
an entire failure. On the 19tli of April in this year, 1880, Mr. Anderson 
had the soil dug over, and the ground again sown with Carrot seed, 
and in order to experiment, after the seed was sown, the beds were 
beaten quite firm, and lightly covered with soil as above-mentioned. 
A good dressing was then given with wood-aslies, in which paraffin oil 
had been mixed in the proportion of one quart to a barrow load of 
ashes—about one cwt. When the plants were about four inches high, 
a second dressing of the same mixture was given, and Mr. Anderson 
says he can state that he never lifted a better crop of Carrots. In 
other parts of the garden, where they were dressed with wood-aslies 
alone, the Carrots were badly affected. Mr. Anderson mentions that 
he thinks that mixing the paraffin with some absorbing substance is 
better than simply watering with a solution of it, as it lasts longer, 
