. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 84 BULLETIN 803, U. S. DEPARTMENT OF Fig. 6.—Phylloxera vitifoliae: Intermediate of type 2, ventral view. Much enlarged. fore visible from above. In group 1 were two individuals collected on young vinifera vines. One of them greatly resembled an adult wingless radicicole, but be- sides the larval eyes it had two to three extra facets, and the antennae and legs were longer than in the radicicole. The other was slender, re- sembling a prenymph in shape, and had about six ex- tra eye facets, and one an- tenn
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 84 BULLETIN 803, U. S. DEPARTMENT OF Fig. 6.—Phylloxera vitifoliae: Intermediate of type 2, ventral view. Much enlarged. fore visible from above. In group 1 were two individuals collected on young vinifera vines. One of them greatly resembled an adult wingless radicicole, but be- sides the larval eyes it had two to three extra facets, and the antennae and legs were longer than in the radicicole. The other was slender, re- sembling a prenymph in shape, and had about six ex- tra eye facets, and one an- tenna showed two sensoria. Group 2 (fig. 6) had six rep- resentatives, all with small to very small rudimentary wing pads invisible from above. In all cases the antennae (fig. 8) and legs were long, and one insect had two sensoria on antennal segment III. In shape the individuals resembled wing- less radicicoles. One specimen (from Wyoming Red) had no extra eye facets, and the others from young viniferae had a varying number, usually 10, although one had about 15. The remaining 9 individuals came under group 3 (fig. 7), and, because of their more pro- nounced nymphlike characters, these are more easily observed in life upon roots than are those of the other two groups, and 4 of the 6 individuals rec- ognized alive on roots were of this type. It is probable, judging from random collections, that the insects of groups 2 and 3 are about equally abundant and each somewhat more so than those of group 1. All the in- dividuals of group 3 had rudi- mentary wing pads, in many cases almost as large as the wing pads of the nymphs. They bulged out from the sides of the insects, and were soft and appeared coiled (fig. 7) or curled. The com- pound eyes were well developed, there being from 66 to 100 per cent as many facets as in the nymphal eyes. In some cases the larval. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability
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