1/6 MAINE AGRICUL<TURAL EXPERIMENT STATION. I912. 



Fig. 295. 



Fig. 297. 



Oviparous female. This yellowish form is about 1.4 mm in 

 length. It is beakless and the antenna is 5-jointed. Fig. 296. 



Apterous z'k'iparous female. Large dark form about 4.6 mm 

 in length, and as woolly as Pemphigus tessellata. Antennse with 

 I subequal to 1-2 II; II subequal to 1-2 III; III, IV, V, VI 

 approximately subequal. 



Aphis gladioli Felt. Collection 84a-o8 made from stalk of 

 Gladiolus Orono, Sept. 15, 1908, comprised alate viviparous 

 females of this species which accords in every detail with named 

 examples of gladioli Felt given me by Dr. E. P. Felt. 



Concerning the life history of this species Dr. Felt says (24th 

 Report of the New York State Entomologist); "Gladioli bulbs 

 are kept by growers in, large ware houses, the temperature 

 being maintained at about .jo degrees throughout the winter. 

 This_ insect is evidently unable to breed under these conditions. 

 As spring advances and the house begins to warm up in March, 

 the aphids appear in large numbers, reproducing so abundantly 

 that the window frames and. sills may become literally covered 

 with wings and bodies of plant lice. It is comparatively easy, 

 in a barly infested house, to sweep up a gill of wings and 

 exuviae from imder one window. This plant louse multiplies 

 freely upon tlie bulbs, usualh' being massed around the origin 

 of the roots, and sometimes nearly covering the entire under 

 surface. Breeding evidently continues from some time in 

 March until July, with the production of numerous winged 

 individuals the latter part of July, at least in the case of bulbs 

 submitted for examination, though winged females itndoubtedly 

 occur earlier in the season under warehouse conditions. Bv 



