242 



THE AMERICAN ENTOMOLOGIST. 



80) only, and is indicated by the dotted 

 line — the small scale at the top refers to 

 it. In the full scale at the top of the page 

 the rainfall also is given in variations from 

 the mean only. 



The high temperature of 1854, '71 and 

 '74, together with the diminished rainfall, 

 furnish the key to the cause of the great 

 development of the Chinch-bug during 

 these years. 



ADDITIONAL EXPERIMENTS WITH 

 PYRETHRUM. 



The following experiments were made 

 at our instance by Mr. H. G. Hubbard, at 

 Centreville, Fla., to show the effect of 

 California Buhach (Pyrethrum) powder on 

 young Aletia larvae, the object being to 

 ascertain the minimum quantity that could 

 be used with effect. 



All the larvae were hatched last night 

 from eggs laid in breeding jar during the 

 night of Aug. 7th (except larva [//], which 

 was only a few hours from the egg). 



(a). Three minute fragments of Pyrcthriini laid 

 upon back (terminal half of bod)') with the 

 point of a needle, larva affected in 15 sec- 

 onds; convulsed in i minute and 15 seconds. 

 Died in p. m. 



(l>). One minute fragment applied on back (ante- 

 rior segments); fragment dropped off in 3 

 minutes ; probably only adhered to hairs of 

 body iYt, minutes ; larva appeared affected 

 but slightly ; after three hours larva appears 

 to have recovered. P. M., went to eating 

 and fully recovered, This is a very vigorous 

 larva, probably several hours older than the 

 rest. (Aug. 12. ; has grown larger, and eat- 

 ing well. ) 



(f). One almost microscopic fragment applied, 

 with needle point, to side near spiracles ; 

 evidently affected in 15 seconds ; convulsed 

 in i^ minutes. Fragment adhered one min- 

 ute. Larva died in p. m. 



((/). One very minute fragment (almost micro- 

 scopic fragment) applied on side of body 

 near middle. Larva lost sight of during 4 

 minutes, at end of which time was entirely 

 convulsed. Died in p. M. 



{e). Several (3 or 4) small fragments applied on 

 side of body ; affected in 30 seconds ; con- 

 vulsed after 2 minutes 15 seconds. Died in 

 p. M. 



(/). One minute fragment on middle of back ; 

 affected in i minute 15 seconds ; convulsed 

 in 3 minutes ; fragment dropped off in 3 min- 

 utes. Four o'clock, p. m., larva recovering ; 

 later, went to eating ; entirely restored. 

 (Aug. 12, alive and well.) 



{g). One microscopic fragment on back at anal 

 extremity of body and very soon lost off 

 (20 seconds?). Seemed affected after 5 min- 



(/')• 



(/'). 



(/)■ 



(;«). 



(."■'). 



utes ; examined after 2 hours, seems not 

 injured. In p. M., entirely well [see (^'')], 

 One large fragment (size of "blowfly" egg) 

 applied for 5 or 6 seconds to side of body, 

 near or upon spiracles ; affected in 2 minutes; 

 convulsed in 4 minutes ; 2 hours, unable to 

 move about ; 4.30 p. M., still alive but dis- 

 abled. Died before night. 

 One entirely microscopic fragment applied to 

 back of neck ; affected in i}4 minutes ; con- 

 vulsed in 3 minutes; 4.30 p. m., appears 

 recovering. (Aug. 12th, larva died this 

 morning.) 



One entirely microscopic fragment applied 

 underneath anterior segments between legs ; 

 adhered only a few seconds ; appears affected 

 after 15 minutes, but able to move about. 

 4.30 p. M., recovering and eating; later, fully 

 recovered. (Aug. 12, alive and well.) 

 ■:. — Larvrc (/,) (;«,) and (;/,) were treated as 

 follows : A small quantity of Pyrethrum 

 placed on a piece of paper was lightly sprayed 

 with an atomizer, and allowed to remain cov- 

 ered with drops of moisture for about 10 

 minutes. The larvfe were then touched with 

 a needle dipped in this poisoned dew. 

 A single, very slight, and probably insuffic- 

 ient application beneath anterior segments ; 

 no moisture adhered to larva ; affected after 

 I minute 15 seconds ; i hour later, appears 

 torpid but not convulsed. 4 p. M., recovered 

 and eating. (Aug. 12, alive and well.) 



Touched with poisoned dew about anterior 

 segments, and moisture left upon the back 

 of the segments ; more thoroughly applied 

 than in preceding larva ; affected in 45 sec- 

 onds ; convulsed in 2 minutes. 4.30 p. m., 

 recovered. (Aug. 12, alive and well.) 

 A very young larva, probably hatched late 

 this morning, was allowed to crawl along 

 needle and over a drop of poisoned dew ; 

 instantly affected ; convulsed in 15 seconds. 

 Died in p. M. 



Second experiment with larva (o) made in 

 P. M. One fragment, size of blowfly egg, 

 laid on back, middle of body, not touching 

 the skin, but adhering to hairs, dropped off 

 in 30 seconds ; evidently affected in 45 sec- 

 onds ; completel}' convulsed in 2 minutes. 

 Died in a few hours. 



A NEW ENEMY TO THE STRAWBERRY. 



Prof. A. J. Cook, of Lansing, Mich., pub- 

 lishes in the Lansing Republican, of June 24, 

 1880, an interesting article read before the 

 Ingham County Horticultural Society, giv- 

 ing an account of a Strawberry leaf-beetle 

 {Faria aterrwia Oliv.), with descriptions of 

 the insect in the larva, pupa and imago states. 

 This is a small, brownish leaf-beetle, which 

 we have known to injure strawberry leaves 

 for the past six years, having found it with 

 this habit in southern Illinois and Missouri, 

 and having received it in the Fall of 1874 

 (Oct. 5) from the esteemed horticultural 



