REPORT OF THE STATE ENTOMOLOGIST 225 



colony. It is stated that several of the young have been seen upon the 

 wing-covers of a single lady-bird, that they are often found on ants, and 

 that they show a preference for insects of dark color. 



Distribution in Nursery Stock. — The ease with which many of our most 

 serious insect pests may be widely distributed through sales of nursery 

 stock, has been brought to notice so frequently in recent years by studies 

 made of the means by which injurious insects have suddenly made their 

 appearance in new localities, that our economic entomologists have 

 deemed it their duty from time to time to warn fruit-growers of the 

 danger to which they are exposed, and to impress upon them tlie great 

 importance of a thorough inspection of all the nursery stock purchased 

 by them. Each of the recent occurrences of the San Jose scale in the 

 Eastern States, has been traced directly, or with a strong probability, to 

 nursery infestation as its source. Of course, the danger of such intro- 

 duction is the greater when the insect is so inconspicuous as is this scale, 

 or when it is entirely hidden within its bvurows in the branches or trunk, 

 as in the case of the flat-headed pear tree borer, Agrilus sinuatiis Ohv., 

 lately discovered in New Jersey orchards by Dr. Smith, and by him 

 traced to a New Jersey nursery which it was supposed had imported it 

 from Europe about ten years ago. 



Protection from Infested Stock. 



In view of this danger, the following suggestion made by Dr. Smith 

 {Entomological News, v., p. 311) is both timely and important : "No 

 farmer should set out a tree until he has examined it closely and made 

 certain that no scale-insects infest any portion of it. He should also 

 wash at least the trunk and larger branches with a kerosene emulsion, 

 diulted by no more than five parts of water ; and he should, finally, trim 

 back to the smallest possible amount of wood, burning or otherwise de- 

 stroying all the cuttings," thereby facilitating the growth of the tree, and 

 disposing of the eggs of the Aphides or plant-lice and of mites occurring 

 on the smaller twigs. 



Dr. Smith also offers the following: "Purchasers of nursery stock 

 could insist on a written guarantee with each lot of stock purchased, that 

 they are clean and free from insect pests, and had not been, in the 

 nursery, affected by any plant disease, nor grown in the vicinity of dis- 

 eased trees." 



It is not probable that the New Jersey or Long Island nurserymen 

 would give such a guarantee, nor does it seem that they could safely do 

 so. Were they, one and all, skilled entomologists they might even then, 



