114 



Observations on the various Insects 



Aphis Mapa?, A. Humili, A. Persies, A. Eabce, and Schizoneura 

 lanigera. 



It is only when the plant-lice take possession of a plant, breed 

 upon and smother it, that they can affect its life. 

 It is by suction they exhaust vegetation. 



Lady birds and their larva, the maggots of dipterous flies, and 

 some small hugs, live upon the plant-lice. 



A fly called Sapromyza obsoleta supposed to cause the potato- 

 rot, laying its eggs in the young shoots. 



Thrips minutissima accused of causing the potato epidemic. 



They live by suction, and never are in sufficient numbers upon 

 the potato-leaves to affect the tubers. 



A minute ground-flea, Smynthurus Solani, feeds on the pulp 

 of the leaves. 



A Smynthurus in Nova Scotia destroys the very young turnips 

 and cabbages. 



They generate upon old cultivated ground, and damp drives 

 them away. 



Salt or sea- weeds scattered over the ground will expel them. 



A Podura feeds on the pulp of the leaves, and is supposed to 

 -poison the sap. 



Plant-bugs believed to cause the potato -disease. 



Lygus Solani. L. contaminatus. L. bipunctatus, L. umbella- 

 tarum, Phytocoris pabulinus, and P. viridis, were the accused 

 species. 



Another species appeared 10 years earlier in the United States, 

 where similar opinions were entertained of their poisoning the 

 votatoes. 



Frog-flies, called Eupteryx Solani and E. picta, breeding on 

 the potato-haulm, and accused of destroying the potato- crops. 



They live by suction, as well as the plant- bugs, from the time 

 they are hatched to their final state. 



Macrocnema exoleta, a leaping beetle, feeds upon and riddles 

 the leaves of the potato and bitter-sweet. 



Caterpillars of the deatlis-head sphinx feed upon potato-leaves. 



This moth robs bee-hives, and is called also the bee-tiger. 



An Ichneumon fly, Trogus atropos, lives in the caterpillars of 

 the deatli s-head moth. 



A mite, Oribates castaneus, congregates on the dead potato- 

 haulm to feed on fungi. 



M, Guerin attributes the potato -disease to atmospheric changes, 

 and not to insects. 



Surface-grubs, the caterpillars of moths, Agrotis exclamationis 

 and A. segetum, destroy potato as well as turnip crops. 



Maggots of Tipula? ; the crane-flies or daddy-longlegs, seriously 

 affect the potato-crops. 



