. Bulletin of the Department of Agriculture. Agriculture. THE RED SPTDER ON COTTON, 11 SECOND NYMPHAL STAGE (THE DEUTONYMPH). Description.âThe doutoiiymph, which occurs only in the case of the female, resembles the protonymph except that it is larger and more elongate. In the advanced condition of this stage (PI. II, fig. 4) it also resembles the adult female. Although pigmentation is intensi- fied as the mite approaches matiu^ity, there is usually an absence of the characteristic reddish color. As the deutonymph approaches matu- rity it can be distinguished from the maturing male nymph,
. Bulletin of the Department of Agriculture. Agriculture. THE RED SPTDER ON COTTON, 11 SECOND NYMPHAL STAGE (THE DEUTONYMPH). Description.âThe doutoiiymph, which occurs only in the case of the female, resembles the protonymph except that it is larger and more elongate. In the advanced condition of this stage (PI. II, fig. 4) it also resembles the adult female. Although pigmentation is intensi- fied as the mite approaches matiu^ity, there is usually an absence of the characteristic reddish color. As the deutonymph approaches matu- rity it can be distinguished from the maturing male nymph, as the lat- ter is smaller, more cuneate posteriorly, and exhibits a tinge of amber or ferruginous. A series of measured deutonymphs averaged, length, mm.; width, mm. Duration of the deutonymphal period.âPerkins (1897) found that in Vermont an average of 2 days was required for the completion of the second nymphal stage under summer conditions. Ewing's 5 completed deutonymphal breedings averaged days. The portion of this interval occupied by the quiescent period (the " Teleiochrysallis" of von Hanstein) is not clearly indicated in Ewing's bulletin, but appears to be approximately 1 day. In the Batesburg investigations 25 colonies completed the second nymphal stage of the female. One deutonymph, the egg of which was deposited on September 27, required 13 days for its development. Exhibiting the other extreme, a few individuals of this stage matured in ap- proximately days in midsummer. The aver- age duration for the second nymphal stage during â 1 .. ⢠1 rk 1 Fig. 3.âCast skin of the the active season is days. ,^^ .pj^^, ,1^^^ ^t ti,. Habits.âThe deutonymph is probably the time of second moit, stm » , 1 ⢠. â¢, ; united by the ventral most voracious ol the immatm-e mites, it roves ^5^^^^^ (Original.) about considerably on its native leaf. Ewing (1914) records a well developed spinning ability on the part of the deutonjnn
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