76 
two dates, Mr. Ratlift’s notes give the following record of minimum temperatures 
through which the insect must have necessarily passed. 
September 23: (frosh) cee bee oe ctccte canaica owes ene eee eee ene 26° 
October.G\(Mohttrost) eco. besa acer c see eee eee ae ea eee 26° 
October 17 (hghtirost) <s- <a h ani cee Seb eos G ae ee eee a eee 34° 
October 12 ight Trost) —.o.s222 Sos e oe sec ne oka a elee eee eee mee 26° 
‘Octoberl4(heavyarost)* aces: Giet ctecce. ec ee eeiseacee mae eee 24° 
October 5(Gast) ih esses ss cneet Caese oom Sa Dee nae anata eae eee 26° 
OstoberaG (Mehttrost). 5.2 gecce os cede. ocecenlee ene cece Ree ee 29° 
Rains on September 11, 26, October 10. Total precipitation during September and 
October, 2.50 inches. 
At La Fayette, the same year, I found adults ovipositing on November 3, but of the 
origin of these flies of course nothing wasknown. The temperature through which 
these must have passed, supposing the eggs from which they evolved were deposited 
after September 1, was as follows: i 
Min. temp. 
Septemberi2s ts-< cc dear Ws seeeioe eee ae ines a Sen ei ee eee ee ee 39° 
Esepiembenca((hirst irost)|-ss< sane cece ee eee once eee ee eee eee 
OGtoberd eso S see, Foe este em See ese ke er oe 39° 
October U2\(Grost) sips. tenho ccna p ieee cee coneee peers eee eee 7H)2) 
October 14 (frost) 22.6. 22 cone wees costes eee eee eee eee Eee 
Octoberd d ((EOSt) ie te 8. acc stele ciserace cee RSE ne eet eee eee ene 31° 
(OYG (0) 82) is OR eee a een cr a Meer rt So SOL AAs Gone 38° 
OctoberdOY(Grost) eos. o- 8 eee sees once eee eee ee eee ee eee a2 
October, 20°(ightisnow).jseseeas nee eee coats eee ee ee oe eee 37° 
Me halver Ol Feist kta aioe Aide foe ee See eee Ie ee ee 29° 
Octoperie2 ssceih sais fe te se eeiserd wae dae bere See Cie Get eee eee 219 
October olChrost))\2sc.01 cis.5 See Nao Sai eae Re eee 132 
October 2GK(irost) se oe acece ess see cee eee ee pee eee 
October aMrost) 22.2 see eae ee ae eae eee ea Eee eee 21o 
October 28 Grost) 4.5 tea ee Se ets eee eS ee 28° 
October 2b. Fast o. Pi girs ete Ue eee eee Ceo ee eer eee 33° 
Octoberis0 rost) s sce: Sac Seis oot ese Sec heee e eee eee oe ee eee 13S 
October Se sencc232s0 hs Se ceee es ces Ge yeaa eee eee eer EOE 28° 
Noeyember' (trout) 22. << dsswe se diee ce oS Sea. ea abn ee eee aes 28° 
Novemberi2"(frost) cae sesacoce cea smereninoee ceca eee Eee EERE ems OS 
Novermber!s (rest). cane cascs esse een eos eeee cece sae Seeeene ee 32° 
Rains on September 7, 13, 14, 22, 27, 28, 29, 30, October 3, 9, 10, 12, 
23. Total rainfall, 4.64 inches. 
From this it will be observed that the adult flies may emerge and 
oviposit under what we suppose to be very adverse circumstances. To 
what extent the eggs and young larve are able to withstand such 
weather I have no facilities at present for demonstrating. The major 
portion of the small brood of flies, however, emerge during a more 
favorable period, and for meteorological aid against these we can only 
look to the dry, hot weather of July and August, though to the south 
a portion of September might be included. But the straggling indi- 
viduals, which, as I have proved, may originate from stubble, volunteer, 
or even early sown grain, and which I myself can find no satisfactory 
reason for not considering either the retarded or accelerated individuals 
of either one or the other or both broods, have it in their power to repro- 
duce a considerable progeny, which, though of themselves not a serious 
