22 MISCELLANEOUS RESULTS OF WORK OF BUREAU— IX. 



species was found devouring those of its own kind. The molted skin 

 is usually eaten. A chest of old clothes, which had been wet in a 

 flood, was found to be literally alive with this sowbug. Experiments 

 with eggs of the cattle tick (Boophilus armulatus Say) gave the fol- 

 lowing results: Four sowbugs provided with over 300 eggs devoured 

 153 at the rate of between 5 and 6 a day each. 



The broods of this species are small, numbering from 8 to 30. 

 Metamorphosis is more rapid than in Armadillidium. The seventh 

 pair of legs is attained before the twelfth day. Molting is as in 

 Armadillidium. 



The same remedies as recommended for Armadillidium were found 

 to be effective. 



METOPONORTHUS PRTJINOSUS Brandt. 



Metoponorthus pruinosus Brandt is a much rarer sowbug than 

 either of the two preceding species. It is also more delicate and more 

 agile. The color is a beautiful blue-gray in the male and somewhat 

 tinged with red in the female. Its haunts are damp, earthy places 

 in sheds, etc. 



These sowbugs feed very eagerly on cotton leaves and were kept 

 under the same condition as the two preceding species. Forty tick 

 eggs were eaten by two individuals at the rate of about 7 per day 

 each. They may be poisoned by dusting the soil in their haunts 

 with arsenicals. 



Keproduction and development is very rapid, much more so than 

 in either Armadillidium or Porcellio. One pair produced four 

 broods of young in sixty-two days, there being seventeen, sixteen, 

 and twenty-one days between broods. The broods are small. The 

 young grow so rapidly that in two months they are one-half as large 

 as their parents. They molt frequently. It is very difficult to ob- 

 serve this species closely because of its rapidity of movement. 



CONCLUSIONS. 



In conclusion it may be said that (1) in a damp year the sowbugs 

 may do considerable damage to the young growing vegetable crops; 

 (2) they serve at all times as scavengers; (3) their exclusion from 

 houses is advisable because of the scavenger habit, there being a 

 possibility of the transmission of diseases; (4) in the case of the 

 cattle-tick problem they may be beneficial by eating such eggs as are 

 deposited in barns, sheds, pens, in the woods near the watering places, 

 and in moist meadows. Finally, cleanliness is probably the best pre- 

 ventive against sowbug inroads, arsenical compounds the best outdoor 

 remedies, and carbon bisulphid the best indoor remedy. 





