232 MAINE AGRICULTURAL EXPERIMENT STATION. 1916. 



Egg. Of the usual shape, less pointed anteriorly than that of Allo- 

 grapta obliqua (Fig. 31-61, 62). Length of twelve eggs measured, ranged 

 from .91 mm. to 1.015 mm., with an average of .958 mm.; the maximum 

 diameter from .32 mm. to .37 mm., the average .34 mm. Color, chalk 

 white, sculpturing similar to that of A. obliqua (Fig. 31-65) but the ele- 

 vated bodies a little shorter and broader than in that species, about two 

 or three times as long as broad; distance between bodies about half 

 their width; number of arms around each, 12 to 20; rather short, not 

 much branched, many ending at half the distance across the intervening 

 space. Number of bodies around the egg at the middle about 50; number 

 the length of it about 30. 



Duration in the egg stage about two or three days. The 

 eggs are laid singly at short, varying intervals of time. In 

 captivity the female always moved about after each egg was 

 laid before depositing another. The actual process of placing 

 the egg is speedily accomplished, the egg slipping out of the 

 much extended ovipositor very quickly. The end is touched 

 to a leaf where the "glue" fastens it and the ovipositor is then 

 quickly drawn away from it, retracted, and the fly crawls away 

 some little distance when the process is repeated. In the field 

 the insect flies about from place to place, occasionally resting 

 briefly on the under side of a leaf for the deposition of an 

 egg. This habit of scattering the eggs of aphidophagous 

 species is of value in preventing the too great congregation of 

 larvae and consequent scarcity of food. In captivity the insect 

 frequently rested and manipulated the extended ovipositor with 

 her hind legs, rubbing the metatarsi over it. Whether this is 

 a natural habit or induced by some artificial condition (as, pos- 

 sibly, contact with the sugar solution supplied as food) I ao 

 not know. The female laid eggs at the following rate: 4 

 minutes, 7^ minutes, J minute, f minute, 2.\ minutes. About 

 60 eggs were laid by a female taken in coitu and kept confined. 



Larva. (Fig. 31-76). Length 9 to 10 mm., height 1.25 mm., width 

 2.25 mm. Elongate oval, tapering at anterior end, somewhat truncate 

 except for respiratory appendage at posterior end, depressed. Outline 

 irregular, dorsal integument much wrinkled transversely, and with lateral, 

 longitudinal carinae. Color pea-green with two, narrow, longitudinal, 

 white stripes, laterad of and paralleling the rather conspicuous dark 

 heart-line. The stripes attenuated and confluent a little before the an- 

 terior end, not reaching the respiratory appendage posteriorly. Respira- 

 tory appendage brownish black at the tip. The skin papillose, bare 

 except for the usual segmental bri/stles which are here short, light- 

 colored and inconspicuous. There are a number of poorly denned pro- 

 leg-like projections of the body on the ventral side. The mouth-parts 



