. Bulletin of the Department of Agriculture. Agriculture. THE RED SPIDER ON COTTON. 57 There is a larval period of 24 days, requiring 4 iiistars of 7, 3, 4. and 10 days, respectively, and a pupal period of G days, altogether embracing an interval of 30 days from hatching to the issuance of the adult. Table Ist day 2d dav 3d day da\- 5th dav 6th day 7th day (molted).. 8th dav 9th day 10th day (molted). -Feeding capacity of Mcgilla maculata for red-spider adults, Bateshurg, S. C. (Eggs hatched Sept. 11, 1914.) Mitci. 7 7 9 17 22 25 31 48 63 75 Mites. 11th day 80 12th day 100 13th
. Bulletin of the Department of Agriculture. Agriculture. THE RED SPIDER ON COTTON. 57 There is a larval period of 24 days, requiring 4 iiistars of 7, 3, 4. and 10 days, respectively, and a pupal period of G days, altogether embracing an interval of 30 days from hatching to the issuance of the adult. Table Ist day 2d dav 3d day da\- 5th dav 6th day 7th day (molted).. 8th dav 9th day 10th day (molted). -Feeding capacity of Mcgilla maculata for red-spider adults, Bateshurg, S. C. (Eggs hatched Sept. 11, 1914.) Mitci. 7 7 9 17 22 25 31 48 63 75 Mites. 11th day 80 12th day 100 13th dav 96 14th day (molted) 76 loth dav 83 16th day 97 17th day Ill iNthdav 135 19th day 156 Mites. 20th day 218 21st dav 206 22d dav 224 23d day 24th day (pupated). Total - 2,011 Average daily con- sumption From Table XXV it may be seen that 1 individual in 23 feeding days ate 2,011 adult mites, thus averaging mites per day. There are probably 3 or 4 generations of this coccinellid in a season in the Fig. is.—The convergent lady-beetle (Hippodnmia cnnvcrgens), an enemy of the red spider: a, .\dult: h, pupa; c, larva. Much enlarged. (Chittenden.) HippodaTYiia convergens Guerin.—This species (fig. 18) is perhaps the commonest of the ladybirds in the Southeast. We have seen it on a few occasions busily engaged in consuming the members of mite colonies. We have conducted no special tests with this beetle, either for life history or control efficiency, since we do not consider that it normally spends much of its time in the quest of red spiders. A new- born hirva of this species on one occasion ate27 adult mites in24hours. As compared with Miss Palmer's (1914) life-history records for this species, we obtained 3 days in 2 cases for the egg period and 7 and 8 days in 2 cases for the pupal stage, as against 3 days and 4 or 5 days, respectively, for her experiment.^. The fact that the summer adults of the larger lady-beetles live from 2 to 4
Size: 2197px × 1137px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
