. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 32 BULLETIN 4M, U. S. DEPARTMENT OF AGRICULTURE. at :in\- distance from the host plants. In the laboratory, however, the adults often gather in small colonies upon the ceiling. THE EGG. DESCRIPTION. The egg (fig. 2) is pure white, about 2 mm. long, elongate elliptical, nearly flat on the ventral surface, more convex on the dorsal. Eggs are often some- what curved. DURATION. The duration of the egg stage of the melon fly is very short. Dur- ing the warm summer weather of August, 1914, when during the developmental perio
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 32 BULLETIN 4M, U. S. DEPARTMENT OF AGRICULTURE. at :in\- distance from the host plants. In the laboratory, however, the adults often gather in small colonies upon the ceiling. THE EGG. DESCRIPTION. The egg (fig. 2) is pure white, about 2 mm. long, elongate elliptical, nearly flat on the ventral surface, more convex on the dorsal. Eggs are often some- what curved. DURATION. The duration of the egg stage of the melon fly is very short. Dur- ing the warm summer weather of August, 1914, when during the developmental periods the average mean tempera- ture of Honolulu averaged ° F. and the aver- age range in temperature was only °, 267 eggs hatched in from 26 to 35 hours after deposition. Of these eggs, which were deposited during a period of 1 hour, as shown by the data in Table V, 149, or slightly over per cent, hatched within from 26 to 28 hours after deposition. "When the average mean temperature for the incu- bation period averaged ° F. and the daily range in temperature about °. 84 eggs de- posited between and p. m. on May 19 hatched between 10 p. m., May 20, and 2 a. May 21, or within from 31 to 38 hours after dep- osition. At a mean temperature of about 75° F. 96 eggs hatched within from 33 to 38 hours after deposition. At the still cooler average mean temperature of ° F. 88 eggs hatched between from 10 to 50 hours after deposition. While the data included in Table V give infor- mation regarding the duration of the egg stage in Honolulu or littoral Hawaii in general from April to November, other data show that during January to March embryonic development may require at least 3 to 4 days when the mean temperatures drop to about 69° F. At higher altitudes this period may be appreciably prolonged, due to still lower temperatures, although it is unlikely that at any place where the melon fly is found in Hawaii the duration of the egg stage is
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