DUFFEY TRANSFORMATIONS OF A CARABID, ETC. 537 



three : one on the third or fourth day, the second four days later, 

 and the third at the time of pupating, nine days later. 



While I did not succeed in rearing perfect insects from the 

 eggs found in Hyphantria webs, there is no doubt that the lar- 

 v£e hatched from the above eggs were identical with those found 

 in the webs, and from which adults oi Plochtomcs timidus were 

 reared. 



I have not been able to determine the state in which this insect 

 hibernates. These observations seem to indicate that it passes 

 the winter as an imago, as all of the observed larvaj of the second 

 brood either reached that state or died. While some of the larvae 

 dug somewhat into the sand before pupating, they did not pupate 

 there ; and those that were left undisturbed in the web were not 

 observed to leave it. The larvte which were seen to dig into the 

 sand were disturbed daily by removing the debris left by the web- 

 worms so that the Plochioiius larvae might be more closeh' ob- 

 served. This is also probably the reason that all of the larvae 

 hatched from eggs did not go through all of their transformations, 

 since of those brought in with the webs and not disturbed in the 

 breeding-cage by removing any of the web, nearly all reached 

 the imago state. There may be another brood than those stu- 

 died, which might hibernate as pupte, provided the species has 

 other food habits than those observed ; but it is not possible 

 for another brood to have reached the pupal state in the Hyphan- 

 tria webs. Six beetles of the sceond brood, kept in a breeding- 

 cage with web-worms, died without laying eggs. If Plochiomis 

 has no other prey, it is strange that its transformations should 

 have so long escaped observation, since the web-worm and its 

 enemies have received considerable attention.* Yet this may be 

 due to the local or temporary rarity of this insect at the time the 

 published observations were made.f 



* See Riley, 3 Mo. Report; and Report of Entomologist for 1SS6. 



t The morning after this paper was presented to the Academy I received a letter from 

 Miss Mary E. Murtfeldt of Kirkwood, Mo., who is interested in economic entomoloey, 

 and whose attention I had called to this insect early in the season with a view of learning 

 if she had made any obser\-ations on it, from which I quote the following: — 



"Had you not discovered this valuable little Carabid, I should have done so, as it 

 appeared in Kirkwood on the second brood of Hyphantria ctmea, and in many instances 

 depopulated the webs. Small as they are, I have seen these larvae seize hold of an almos 

 full-grown worm and not let go for all the contortions of the latter. I have also found them 



