. Bulletin of the Department of Agriculture. Agriculture. 36 BULLETIN 491, U. S. DEPARTMENT OF AGRICULTURE. slightly rounded, bearing 18 or 20 lobes, as illustrated in figure G, a. Pos- terior Rtiginal plates very evident, not appreciably elevated or depressed, ap- proximate, each with three well-chitinized slits pointing toward those of the ()l>l)osite plate as illustrated in figure 9. Slits proportionately longer and narrower than in either of the other instars. The fine bristles about nuirgin of stignial plate arranged in four sets, relatively finer and shorter than in the seco
. Bulletin of the Department of Agriculture. Agriculture. 36 BULLETIN 491, U. S. DEPARTMENT OF AGRICULTURE. slightly rounded, bearing 18 or 20 lobes, as illustrated in figure G, a. Pos- terior Rtiginal plates very evident, not appreciably elevated or depressed, ap- proximate, each with three well-chitinized slits pointing toward those of the ()l>l)osite plate as illustrated in figure 9. Slits proportionately longer and narrower than in either of the other instars. The fine bristles about nuirgin of stignial plate arranged in four sets, relatively finer and shorter than in the second instar. Anal opening on venter of last segment, with a rounded protuberance on either lateral side, the entire area including these protu- berances elevated to form a distinct tubercle armed about its base by a concentric area of minute spinules. Body of larva glabrous, except for areas of microscopic spinules -irranged as follows: Hand on Newport's segment cov- ering the anterior two-thirds of the dorsum but widening ventraily to cover the venter; narrower bands extending about the anterior margin both dorsally iiiul ventraily of the second, third, and fourth segments; fusiform bands composed of broken rows upon the venter only of segments 5 to 12. There are no lateral spinulose areas on segments 5 to Fig. 8.—Tho melon fly : Third-iustar larva, a, Lateral view of entire liody ; h, dorsal view of anterior end; c, d, lateral and ventral views of same. Enlarged. (Original.) Dl'KATION OF L.\KV.\I. IXSTAUS. The larva of the melon fly passes througli three instars before be- coming full grown. The number of hours passed in each instar has been obtained for the first 12 larvae recorded in Table VI. These larvffi were transferred daily to fresh pieces of ripe papaya pulp, and were therefore given the best combination of food and tempera- ture for rapid development known lo the writers. The majority of these 12 larva) passed about 1 day in each of the first two instars and ab
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
