283 



maintain itself on native Malvaceous and other plants and this fact 

 should be taken into account when considering methods of control. 

 [See this Review, Ser. A, ii, p. 582, and iv, p. 125.] An account of the 

 life-history, natural enemies and artificial methods of control is given. 

 [See this Review, Ser. A, iii, p. 424.] Spanish moss is stated to be a 

 favourable hibernating medium since it is not readily penetrated by 

 low temperatures, A hst is given of 53 species of birds which are 

 predaceous on this weevil. 



Sanders (J. G.) & Fracker (S. B.). Lachnosterna Records in 

 Wisconsin. — Jl. Econ. Entom., Concord, ix, no, 2, April 1916, 

 pp. 253-261, 3 figs. 



In the experiments carried out in Wisconsin in 1914-15 in connection 

 with Lachnosterna, the factors considered were : — (1) the determination 

 of conditions ; (2) the crops most seriously damaged with and without 

 rotation ; (3) the species present and the habits, life-history, dis- 

 tribution and means of control. Lantern traps were used to collect 

 the beetles. They consisted of the Coleman gasoline arc lantern, from 

 300 to 400 candle power, set into galvanised refrigerator pans, 5 inches 

 deep and 24 inches in diameter. The pans were filled about two- 

 thirds full of water and | pt. kerosene was poured on this and renewed 

 when necessary. Perforated skimmers were used to remove captured 

 insects. Results were obtained relating to the distribution of species. 

 over a comparatively hmited area, the optimum temperature for flights- 

 and the most favourable location and arrangement of hght traps. 

 Seventeen out of the 19 species known to occur in Wisconsin were 

 taken in the traps. L.fusca was most widely distributed and dominant 

 at Lancaster and Dodgeville. L. rugosa was dominant at the north- 

 east stations and L. implicita at Ripon. Males only of L. gibbosa and 

 L. nitida were attracted to the lantern and L. tristis only to a slight 

 degree. Several species disappeared at the stations furthest to the 

 north-east, while L. rugosa, L. diihia and L. grandis increased in 

 numbers. L. dubia emerged very early, before 21st May at Dodgeville 

 and to the extent of 92 per cent, before this date at Baraboo. FHght 

 was found to cease almost entirely at 62° F. Large pans were found 

 to be desirable ; the mmaber of beetles caught in a pan placed by the 

 side of the central pan towards the origin of flight was twice as great 

 as in a pan placed behind the light. At the Lancaster station flight 

 was always from the north-west towards the south-east. Traps 

 near the margin of woods or close to a fringe of trees were most 

 successful. At Lancaster, more than 440,000 beetles were taken during 

 the summer and the maize crop was not noticeably injured. The 

 smallness of the damage may have been due to the destruction of many 

 beetles by diseases and the frequent and heavy rains. The cost for 

 15 light traps was from Is. to Is. M. a day. The numbers of males 

 caught exceeded the number of females. This is the normal condition, 

 and if, as has been suggested, the beetles are polyandrous, there may 

 be an advantage in catching a large number of males. Females of the 

 more common species formed a larger percentage of the catch in the 

 early part of the season than did males. 



In the biological experiments undertaken to investigate the habits 

 of white grubs, glass cages were used in which earth was placed between 



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