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ORDER THYSANOPLERA. 



(Thrips.) 



This order contains almost entirely minute forms 

 of fringed or tasselled-winged insects. The wings 

 are surrounded by minute cilia which form a fringe. 

 Many of the thrips are microscopic; others can be 

 seen as mere lines or flecks, and it is only by means of 

 a microscope or very powerful lens that we can make 

 out anything of their structure. The mouth parts 

 are peculiar, but a pair of sucking jaws can be dis- 

 tinguished. Thrips are found infesting the buds of 

 our roses and carnations in early spring; particu- 

 larly is this the case in very dry seasons. They also 

 attack the opening blossoms of the apple tree, result- 

 ing in some cases in the loss of almost the entire 

 season's crop. Flowers of weeds, grasses, and many 

 of our vegetables, as tomatoes and onions, are 

 not exempt from their attacks. 



Tlie eggs may be deposited in the bud, leaf, stem 

 or even calyx. These hatch in a few days. The 

 larva is a minute form with six legs and a pair of 

 antennae. A brief nymph stage follows, in which 

 wing-pads are developed, and from this comes the 

 adult. The life history of the common thrips found 

 in our roses occupies about 21 days. 



An emulsion of tobacco and soap, or lime and sul- 

 phur, has been found useful, but fumigation seems 

 to be the only real effective means of dealing with 

 these minute insects. 



In addition to the forms already mentioned, we 

 liave in Australia a giant thrip which measures 

 almost half an inch in length. In this species the 



