ECONOMIC IMPORTANCE OF SOW BUGS. 21 



rorv dull. Following the first stage of the molt the anterior seg- 

 ments commence to loosen and are slid forward. The dorsum of 

 the third and fourth thoracic segments is loosened before the legs 

 of these segments are releascvl. From then on the last two pairs of 

 legs in the very 3^oung and the last three in later stages are used to 

 hold the animal in position. The anterior legs are -not available for 

 use for some time after thev are free. The antenna^ are withdrawn 

 last. 



Regeneration of parts takes place in the antenna? and legs. Several 

 times individuals witli aborted members were noticed. These latter 

 would gradually attain full length, then budding of the succeeding 

 segment Avould be noted and finally this member would l)e normal. 

 The regenerated i)art is white for some time. 



KEMEDIES. 



In the treatment of sowbugs poisoned baits are standard remedies. 

 The great fondness of soAvbugs for potatoes long ago led to these 

 being used, poisoned either with Paris green or London purple. 

 The potatoes are sliced and a thin covering of powder applied. 

 Sprinkling the soil around an injured i)lant with Paris green, or 

 dusting the same under boards and other haunts of the sowbugs is 

 also very effective. Tf the sowbugs are injurious in a garden patch — 

 after treating the orclinar}' haunts — it is best to keep the ground well 

 broken and raked to prevent clodding and cracking, which gives them 

 ]H-otection. Old boards, cans, and rubbish should not be allowed to 

 accinnulate. Such jjrecautions will tend greatly to prevent any 

 great damage or ainioyance. 



Carbon bisuli)hid has been reconnnended for the treatment of sow- 

 bugs in greenhouses and dwelHngs. but no special experiments along 

 this line have been tried by the writer. 



PORCELLIO L^VIS Latr. 



Porcellio l(vvi.s Latr. is a lighter colored s()wl)Ug than the preced- 

 ing, and does not roll up in a ball when disturbed, but instead runs 

 rapidly away to cover. The only definite point in favor of consid- 

 ering it as naturally a plant feeder was tlie discovery of one ^V':\i\ 

 specimen under cotton dusted with Paris green. It was found, how- 

 e\-er. that tiie best way to keep this species alive in the laboratory 

 was to furnish it with fresh cotton leaves and h)()se mixed >oil. 

 Sowbugs of this species were not found far from the barns, and were 

 not numerous in the laboratory cotton patch. They were generally 

 under moist, dark objects and seemed to i)refer damp wood j)iles. 

 Several were found with Armadillidium in crevices and in trees at 

 various heights. One Porcellio was found in the skeleton of a car- 

 al)id beetle, which was entirelv eaten out. In numerous cases this 



