. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. THE PEAR THRIPS. 15 Lind.). Botli tlie tliri|)s and the mite were •'^ery common in large onion fields, covering several hundred acres. A mite would be seen to ap- proach and grasp a tlirips with its front pair of legs and, inserting its proboscis, suck out the body juices of its prey. A single mite was often observed thus to kill several thrips within a very few minutes. The writer strongly suspects that some mite preys on the younger stages of the pear tlirips wliile it is in the ground. This would be entirely p
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. THE PEAR THRIPS. 15 Lind.). Botli tlie tliri|)s and the mite were •'^ery common in large onion fields, covering several hundred acres. A mite would be seen to ap- proach and grasp a tlirips with its front pair of legs and, inserting its proboscis, suck out the body juices of its prey. A single mite was often observed thus to kill several thrips within a very few minutes. The writer strongly suspects that some mite preys on the younger stages of the pear tlirips wliile it is in the ground. This would be entirely possible, and mites are commonly found in the grass and in the ground. A fungus, presumably parasitic, has been endemic among thrips during the seasons 1005 and 1906. In its difl'erent stages it lives on both young and mature thrips, and in a way parallels the life of its host. During the spring of 1905 thrips larva^ were often observed to be thickly infesting a tree, and after these had disappeared, presum- ably having gone into the ground, none or but few living ones could be found. Many larvae, too, seemed to leave the tree before they li:i 1 reached full growth, and within breeding cages these larvae were seen to die as the direct result of the parasite. Project- ing from their bodies were to be seen the tiny fruiting conidiophores of the fungus. Adult thrips were seen to be attacked by another form of the para- site during the spring of 1906. The past two seasons have offered almost ideal conditions for the development of the fungus, enabling it to become quite widespread. The life histor3' of the fungus has been determined only in part. The heavy-walled resting spores, the dor- mant stage, are found within larvie and adults in the ground; never, thus far, in pu])9e in the ground or in individuals on the tree. Dead larvae from the ground show that the internal body organs have all been displaced by the fungus, and in most cases the body contains only a mass of the heayv^-
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