r. S. IX A., R. K. I^iil. (i4. 1'iirt TI. Issuod April 2. 1!K)7 



SOME MlSCl^LLAXHOUS RESULTS OE THE WORK OE 

 THE l^UREAE OE ENT0M0L(X;Y-IX. 



NOTES ON THE ECONOMIC IMPORTANCE OF SOWBUGS. 



I'.y W . I>\\i(;iiT I'lERCK. 

 SperidI Field A unit. 



PTaviiig been detailed to investigate certain injuries attributed to 

 sowbugs, the Avriter presents the following notes concerning tlie liiV 

 history and habits of three species of these isopods. namely, Armadll- 

 lidhtm rill (/((!•(' Latr., PorceWto Iwris Latr.. and Metoponorthns p/'ui- 

 iwsiis Brandt. The first species, at least, 4s capable of doing con- 

 siderable injury to garden crops, flower gardens, vines, and field 

 crops in the vicinity of buildings, although it is also found to be a 

 vahuible scavenger. The scavenger habit, however, makes it an unde- 

 siral)le intruder in the house owing to the possibility that it may 

 convey disease. 



ARMADILLIDIUM VULGARE Latr. 



The soAvbug Armadillidiiim rule/are Latr. is commonly known as 

 the " pill-bug." on accomit of its habit of rolling into a ball whenever 

 (listui-bed. Ordinarily it is found only in the vicinity of habitations, 

 in dark, damp places, such as Avoodsheds and cellars, under boards 

 and i-ubbish. and^around Avells, cisterns, and Avater barrels. The open 

 foundations under houses in the South giA'e A'ery favorable locations 

 for breeding. 



For scA'eral years the Department of Agriculture has receiA-ed 

 reports of injury from soAvbugs to one or another cro]) in various 

 parts of Texas. The sowbugs seem to have been on the increase from 

 year to year. In 1905 the spring rains, although at times occasioning 

 a natural check to these pests, brought about a series of conditions 

 favorable to a rapid increase in their numbers. ^loisture is a requisite 

 to their life, and it also seems that A-egetatiqn is a standard article of 

 food. The bad conditions of the ground throughout Texas during 

 that year made all crops very late, so that by the time the succulent 

 cotton and garden crops Avere coming up the ncAv broods of young 

 soAvbugs Avere eA^erywhere engaged in fiuding delicate, tender food. 



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