Insects and Diseases. 1/9 



instance birds were seen devouring, as was supposed, a destructive 

 caterpillar ; but it was found, on a scientific examination, that they 

 were only picking a parasitic insect from the caterpillars. The 

 parasitic insect was assisting the cultivator, and the birds were 

 feeding upon his best friends. One of the most useful insects of this 

 kind is the Lady-Bug of which we repre- 

 sent a single species, the Convergent Lady- 

 Bug, in the accompanying cut (Fig. 506). 

 a representing the larva, b the pupa, and 

 c the perfect insect. We present this figure 

 in order the better to explain an amusing 

 occuirence, showing the blunders of ignor- 

 ance, related by Dr. Fitch. The rose bushes of one of his neigh- 

 bors were grievously infested by plant-lice. He complained to 

 Dr. Fitch, that although he took the greatest pains to go over his 

 bushes every morning and destroy all the "old ones," yet his 

 bushes were ten times as badly injured as those of his neighbors, 

 who took no pains with them. On examination it turned out that 

 he had been killing off the Lady-Bugs, supposing them to be the 

 "old ones," which were doing all they could to rid his bushes of 

 the pest. 



BLACK KNOT ON THE PLUM (p. 1 60) .Remember the old 

 and well tried remedy of cutting off as fast as the first indications 

 appear. Do not wait till the tree is covered with these excres- 

 cences and destroyed. The complaint sometimes made, when the 

 remedy is applied months too late, that cutting off does not cure 

 the malady, would be like denouncing the use of water to extinguish 

 buildings on fire, were the engine companies to begin to play upon 

 the heaps of ashes the year after the city conflagration. The labor 

 and attention needed to keep the plum thus clear of the knot arc 

 not half as great as to keep a potato or cabbage patch clear of 

 weeds, which every one so willingly performs. 



MICE REPELLERS. Generally a smooth, compact mound of mel- 

 low earth, free from grass, and made a foot high, late in autumn, 

 is best. But sometimes a roll of sheet-iron or sheet-tin is most 

 convenient. Sheet-tin is best, and will rust less than iron, unless 

 the latter is well coated with gas tar. Roofing tin, fourteen by 

 twenty inches, will make four protectors to each sheet, seven 

 inches high and three inches in diameter, costing about five cents 

 each. They last many years. They may be applied after some 



