affecting Carrots and Parsnips. 
197 
The maggots of Psila rosce, and probably P, ntgricornis, infest 
them. 
The parsnip and celery miner is a maggot living in blisters on 
the leaves in the summer and autumn, and has destroyed entire 
crops of the latter. 
'J'iiey change to pupai either in the blisters or in the earth. 
The beautiful ^i'fs are hatched in the spring and summer. 
Alysia Apii, a parasite, lays its eggs in the mining maggots, and 
are found in June. 
PacJiylarthrus Siiiaragdiniis probably destroys the direct ^-^a^^- 
site by laying its eggs in the pupaj of the Alysia. 
The mining maggots may be effectually overcome merely by 
pinching the blistered leaves. 
A top-dressing of gas-lime, soot, loood-ashes, or lirne might kill 
the maggots when they bury themselves. 
A lilile flat- body moth called Depressaria Pastinacella, is bred 
upon the parsnips. 
The caterpillars are very destructive to the floicers and seeds. 
Hand-picking and shaking the infested umbels over a sieve to 
collect the caterpillars, are the best remedies. 
The parsnip-plant-louse is found upon the leaves and flower- 
heads, and it is closely allied to the turnip-leaf aphis, if not 
identical. 
EXPLANATION OF PLATE T. 
Fig. 1. A carrot-root affected by "rust," and showing the mining of 
the maggots. 
Fig. 2. The tails of the maggots sticking out, the heads being buried 
in the root. 
Fig. 3. The root divided to show the depth of the injury. 
Fig. 4. The larva of its natural size. 
Fig. 5.* The tail showing the two black spiracles. 
Fig. 6.* The larva or maggot magnified. 
Fig. 7. The pupa of the natural size. 
Fig. 8.* The same magnified. 
Fig. 9. The fly named Psila Jiosce, walidng. 
Fig. 10.* The head in profile, showing the eyes, mouUi, &c. 
«.* The two drooping horns. 
Fig. 11.* Psila RoscB, female, magnified. 
Fig. J 2. A young carrot-root injured by the maggot?. 
Fig. 13. The moth, Depressaria Cicuiclla, at rest. 
Fig. 14.* The same flying, but magnified. 
Fig. 15. The male of Depressaria depressella, the purple carrot and 
parsnip-seed moth at rest. 
Fig. IG.* The female flying and magnified. 
Fig. 11. An umbel of the flowers spun together by (he larva. 
