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northern part of the United States, from the Atlantic to the Pacific, 

 feeds naturally upon plants belonging to the buckwheat family inclu- 

 ding the numerous docks and sorrels (Runtex) and the knotweeds and 

 bindweeds or wild buckwheat {Polygonum) and others. This 

 insect becomes of economic importance Avheu, under certain con- 

 ditions, it finds its way at maturity into apple trees, where it bores 

 into the fruit to hibernate, rendering it unsaleable. It can however 

 only find its way into such orchards as are not kept cleanly cultivated. 

 The possiblity of the larvae reaching orchards from neighbouring 

 meadows, ditch-banks, or road-sides is slight, as they are incapable 

 of finding their way over any extent of bare uncultivated soil. The 

 risk of larvae adapting themselves to the apple is unimportant, as 

 apple foliage is so much tougher and drier than the succulent foliage 

 of the normal food-plants. When the larvae do obtain access to the 

 apples, the injury done is as great as that w^hich caused by the codling 

 moth [Cydia pomonelJa], as a single larva will often bore several holes 

 in a single apple, and sometimes in several, before forming its 

 final burrow. This burrow is often larger than that made by the 

 codling moth larva and is confined to the flesh of the apple. Though 

 not, as yet, a serious pest, it is quite conceivable that it might become 

 so under favourable conditions 



A detailed account of the life-history and habits of T. glabratus is 

 given. There are four generations annually, each occupying about a 

 month, except the fourth, the larvae of which hibernate and complete 

 their development the following spring. Only the larvae of this last 

 generation are known to bore into apples. 



This sawfly is parasitised by the Ichneuraonids, Epinnis pterophorae, 

 Ashm., Spilocryptus sp., Aenoplex sp., Bathymetis sp., Bathyrix sp., 

 and two species of Cratocryptus, attacking the larvae ; the Chalcid, 

 Trichogranima minutum, ^\\., attacking the eggs ; and the Braconid, 

 Rhysipolis sp. It is preyed upon by two Chrvsopid larvae and 

 probably by Coccinellid larvae also. 



Apples may be protected from this insect by keeping orchards free 

 of docks and other food-plants, or, when this is not possible, by banding 

 the trees with cotton or some adhesive substance that will not damage 

 the trees in the latter part of August and leaving the band on until 

 the fruit is harvested. 



McGregor (E. A.) & McDoxough (F. L.). The Red Spider on Cotton. 

 ^U. S. Dept. Agric, Washington, D.C., Bull. no. 416, 29th January 

 1917, 72 pp., 8 plates, 21 figs. [Received 12th April 1917.] 



This bulletin is an amplification of previous papers [see this 

 Review, Ser. A, iii, p. 63, iv, p. 511]. The classification and synonymy 

 of Tetranychus ielarius, L. (bimaculalus, Harvey), are given, with 

 details of its distribution, food-plants and life-history. The nature 

 and extent of the injury to cotton in the southern States and the 

 methods of dispersion and influence of climate are also discussed. 



The list of insect enemies of the red spider is now a considerable 

 one and includes : — 



Acarina. The Gamasids, Seius qitadripilis, Bks., Macrochelis sp., 

 and Laelaps niacropiJis, Bks. , are all important enemies. Rhyncholophus 



