Cynips echinus variety douglasii
agamic form douglasii
Holcaspis douglasii
Dryophanta douglasii
Holcaspis douglasi
Diplolepis douglasi
Disholcaspis douglasii
Dryophanta douglasi
GALL. — Squash-shaped, an irregular, truncated cone attached by its smaller end, flaring distally, with 5 to 11 short, spiny projections from the rim of the distal end of the gall; mature galls pale pink, often with a puberulence which makes them more violet in color. On leaves of (usually) Quercus lobata , rarely on Q. Douglasii. Figures 154-159.
RANGE. — California: 5 miles north of Upper Lake (galls, Hilde- brand and Schulthess in Kinsey coll.). Konocti Bay in Lake County, and Napa County 12 miles southeast of Middletown (Schulthess and Hildebrand in Kinsey coll.). Inskip and Vina (galls, Leach in Kinsey coll.). Scott Valley in Lake County (gall, P. Schulthess in Kinsey coll.). 7 miles southeast of Kelseyville (Hildebrand in Kinsey coll.). Kelseyville (P. Schulthess in Kinsey coll.). Clear Lake, Napa, and Diablo (Leach in Kinsey coll.). Sonoma County (in U.S. Nat. Mus.). Sacramento (gall, in Kinsey coll.). Marin County (Koebele, types). Walnut Creek (C. T. Dodds in Kinsey coll.). Woodland (gall, L. Ewart in Kinsey coll.). Stanford University (McCracken in Mus. Comp. Zool.). Morgan Hill (gall, G. Reed & Z. Cunningham in Kinsey coll.). San Jose (Patterson acc. Fullaway 1911). Byron, Paso Robles and Three Rivers (Kinsey coll.). El Portal (gall, Silvestri in Kinsey coll.). Klink on St. Johns River, and Dinuba (L. H. Powell in Kinsey coll.). Han- ford (E. 0. Essig in Kinsey coll.). Tulare (0. E. Brown in Kinsey coll.). Probably thruout the Great Valley of California, wherever Q. lobata occurs. Figure 23.
The gall of this agamic form is common on the valley white oak, Quercus lobata , thruout the Great Valley of California. The young galls appear late in June (June 28, 1927, near Kelseyville, and July 6 at Diablo in 1922), and many of them are fully grown by the middle of August. Galls collected on September 10 (at Inskip in 1925) were fully grown, but the insects were still so young they could not be bred after collecting. The larvae mature sometime after the first of Oc-tober (before October 4 at Kelseyville and October 16 at Di- ablo in 1925) ; and adults may be found in the galls soon afterwards. The pupal period is short, and for a time in October and November mature larvae, pupae, and immature adults may be obtained from a single collection.
Adults, not yet fully pigmented, were in the galls at Kelseyville on October 30, and on October 29 at Diablo in 1925. These adults do not begin emerging until the end of November (November 26 from Diablo material in 1925, and November 28 acc. McCracken coll.), or after the first of December (December 19-24 acc. Ashmead, and December 18-29 from Diablo material in 1922). Kelseyville material bred here at Bloom- ington, Indiana, emerged out-of-doors early in January (in 1926), and a few of the insects emerged as late as Febru- ary 1 (in 1927). In the field the galls collected by the last of January (at Diablo) are usually empty of insects except for the parasites and inquilines which emerge at later dates. One very large collection made at Diablo as early as December 18 (in 1922) was already empty of gall-making Cynipidae. The records of indoor breedings are usually later: January and February acc. McCracken, and January in my own experience; but it should be noted again that increased temperatures appear to delay emergence in many Cynipidae. The succeeding generation, a form named lobata, appears with the bursting of the buds in March or April.
In November the agamic galls fall to the ground either attached to or separated from the leaves, or the galls remain attached to the leaves which hang on the trees over winter. The galls on the ground are decayed soon after the first of the year, but good specimens may still be found on the trees in the spring (as late as March 7 at Paso Robles in 1920).
Ashmead accredited this insect to Quercus Douglasii, but the fragments of leaves with the type galls are clearly those of Q. lobata. The Douglasii record is copied in most of the literature, altho two students (Fullaway and McCracken) who have known this variety in the field have pointed out that the white oak, Q. lobata, is the real host. Of the several thousand galls which Mr. F. A. Leach collected for me from a number of localities and at all seasons over a period of four years, practically every one came from Q. lobata; but two meager collections, a total of 21 galls found in 1922 at Diablo, seem to have come from Q. Douglasii. My records show that for at least one of these collections I verified the host determination while noting its unique nature. It is, however, inconvenient that an insect that is all but confined to Q. lobata should carry the name douglasii, and the situation is the more unfortunate because the bisexual form of this same insect was named lobata by McCracken and Egbert.
In distribution this variety for the most part parallels echinus, wherever the hosts of the two occur together. But while echinus is replaced by another variety at the higher elevations fringing the Great Valley, I would refer insect and gall material which I have from Lake County to typical douglasii. I have 46 fine insects from Kelseyville alone, and cannot find material differences between them and douglasii unless the Lake County material averages darker. In the consideration of the reality of life zones, perhaps this case should be emphasized as an instance where two, very closely related insects (douglasii and echinus) do not respond in the same way to the same geographic factors.
If there are constant characters by which douglasii may be distinguished from echinus, no one has yet described them. Upon examining a large series of the insects, I find the color distinctions noted by Fullaway are highly variable. The distinctive form of the gall and the host seem to provide the only marks for recognizing this insect. It is surprising that no one has previously adjudged echinus and douglasii to be varieties of one species.
