August, '13] DEW: FALL ARMY WORM 361 



locality before the first flowers were developed, but these without 

 yielding fruit. The floral spike terminating the central axis of growth, 

 two lateral opposite branches developed, but it took two years before 

 the second set of flowers appeared, one spike being a month in advance 

 of the other, and of which the earlier one also remained sterile while 

 the later one produced a small number of fruits, that is, became pollen- 

 ized by some agent adapted for that purpose, during January or 

 February, the hottest summer months in South Australia. To com- 

 plete the cycle of budding, flowering, fruit-setting and ripening it re- 

 quired about a full year, and likewise the cycle of the metamorphosis 

 of the fertilizing insect from the egg, through the larval and (prob- 

 ably) pupal stages, passed within the slow growing fruits. Consid- 

 ering the absolute interdependence of plant and insect, the fruiting 

 here, so far from their endemic home is very remarkable in this case, 

 and appears to be explicable in two ways only, both equally problem- 

 atical. The first is that Pronuha yuccasella larvae were introduced 

 with or imported with Yucca fruit to an Australian locality, where flow- 

 ering Yucca trees existed when the imagines emerged from the pupal 

 shell, in or near the fruits in which the eggs and larvae developed. 



The second alternative is, that an Australian insect exists possessing 

 similar organs, viz., prehensile maxillary appendages and long, exten- 

 sible boring ovipositor, as the Pronuba, which has yet to be proved. 

 I have not yet come across any evidence that either of the above alter- 

 natives has been investigated, and probably no person even lives now 

 that could assist in proving the introduction theory. 



EXPLANATION OF PLATE 8 



1. Yucca aloifolia budding and flowering spikes, looking south, south west. 



2. Ripe fruits, trunk 10 feet high, looking south. 



3. Sterile and fruiting spikes, detached and shown from the reverse side as 

 seen in figure 2. 



FALL ARMY WORM 



Laphygma jrugiperda {S. & A.) 

 By J. A. Dew, Field Entomologist, Auburn, Ala. 



The purpose of this paper is to set forth the facts in regard to the 

 fall army worm which were determined during the outbreak last 

 year. Owing to the fact that previously there has been little investi- 

 gation concerning this species and because the worms are present in 

 local areas again this year, it was thought best to give in condensed 



