Page:The Gall Wasp Genus Cynips.pdf/200

194 may continue to the first of January (January 8, 1922, at Diablo). Some material from Kelseyville, California, was bred out-of-doors at Indiana University in the winter of 1925-26, when emergence occurred between January 15 and January 30, 1926. It is probable that field records would place the bulk of the emergence late in December and in January. McCracken and Egbert give a January record for material bred indoors, suggesting that "This is probably premature emergence"; but with at least many Cynipidae of fall generations increased heat retards rather than hastens emergence.

The succeeding, bisexual generation of echinus is form ribes, to be found in bud galls on the trees in the following March or April.

Late in the fall the galls of echinus fall to the ground, attached to or separated from the dying leaves, but so many of the leaves of the blue oak persist on the trees thru the winter that many galls remain in good condition into the spring (March 7, at Paso Robles in 1920).

The blue oak, Q. Douglasii, is the only host I have observed for this variety, altho I have examined specimens representing twenty-four localities (including material collected on the blue oak by the Fremont expedition in 1849). Fullaway and McCracken, who were in a position to study the material in the field, similarly credit this insect to the blue oak. Osten Sacken described echinus from Quercus agrifolia, and this record has been conscientiously copied without, as far as I am aware, any further proof that this was not a mistaken determination of the host. Bassett made no determination of the host of his speciosus. Kellogg, in his American Insects (fig. 658) states that these galls are on white oak (Q. lobata), but the drawing shows a typical blue oak leaf. Whether this insect will ever be found as a stray on any other oak, it should be recognized that it is now known from Q. Douglasii only.

The insect of this variety seems indistinguishable from that of variety douglasii (q.v.), but the galls of the two will never be confused unless in their very young stages. There is no constant distinction of the gall of echinus from vicina (q.v.), a variety which to a large extent replaces typical echinus in Lake County and at other points fringing the Great Valley. True echinus ranges without appreciable variation thruout the