affecting the Pea-crops, Mangold-wurzel, and Beet. 415 



They probably hatch the end oi May or beginning June. 

 Neither salt nor lime seemed to have the slightest effect upon 

 the larvoe. 



Sea-iveeds and dead animals distributed in a field might decoy 

 them, when they could be destroyed more readily. 



The parent beetles Ccinjly, but the larvoi are hredin thejield. 

 Were the eggs introduced with the seed? 



Seed should be steeped in brine or subjected to heat before 

 sowing, to ascertain if either would free the crop from the larvae. 



Examine the seeds of an infected crop, to learn if the eggs be 

 amongst them. 



Search for the beetles after July upon the stems running to 

 seed. 



From the healthy state of plants accidentally left in the field 

 where the crop was eaten off, it seems possible the plants may 

 recover from the attacks of the larvae. 



Larva of a Shield- beetle, called Cassida nebulosa, feeds upon 

 leaves of mangold-imrzel. 



They reside under the leaves, and also live upon Chenopodium 

 hybridum in July. 



The Shield-beetles hatch the beginning of August. 



A minute parasitic Jiy, one of the Chalcidites, inoculates the 

 larvae with its eggs, which hatch and feed upon the fat, &c. of 

 the victim. 



The Turnip-beetle, Altica nemorum, is now found to feed 

 upon the leaves of the mangold-iourzel as well as on the turnip. 



Larvce of flies greatly resembling each other are often exceed- 

 ingly different in their economy. 



Maggots of Anthomyia Betw discovered feeding on the paren- 

 chyma or pulp in blistered leaves of mangold-wurzel and sugar- 

 beet, the end of June. 



The flies hatched the third week in July. 



The maggots may be destroyed by merely pinching the blisters 

 visible on the leaves. 



They change to brown pupce in the blistered leaves. 



If the maggots do no harm to cattle when the leaves are used for 

 green food, little mischief is likely to arise from their presence. 



Larva of the Crane-fly, Tipula oleracea, is a most destructive 

 maggot in the mangold-wurzel field, carrying off entire crops by 

 eating- through the young roots. 



Not safe to sow mangold-wurzel on fresh broken-up pasture- 

 land, without paring and burning, salting, or liming the soil. 



Rotten places and holes eaten by slugs in the roots of mangold- 

 wurzel are inhabited by swarms of insects, and amongst them are 

 large broods of a little beetle called Cercyou boletophagum, and 

 an AcaruS;, Uropoda umbilica. 



