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ologic data as the galls, it is quite certain that no one would 
arrive at our present classification, and the accompanying host 
and distributional data would then be largely meaningless. 
How much insect taxonomy is inadequate and misleading is a 
matter for serious contemplation. 
That the differences in these agamic galls are not due to 
the qualities of the various oaks on which they occur, is proved 
by the occurrence of three types of galls, the work of three 
different varieties of echinus, on Quercus dumosa in Southern 
California. 
Attention should be drawn to the peculiar, crystalline mate- 
rials of which all these agamic galls are built. Between the 
thin epidermis and the wall of the larval cell there are solid 
masses of microscopic, deformed crystals intermingled with 
a few fibers of similar material. This substance is commonly 
reputed to be gallic acid (as in Fullaway 1911), and if this 
is so, these galls must have a very high percentage of the 
material. It would be interesting to know how the gall in 
its development segregates or stimulates the manufacture of 
this substance in the normal oak leaf. When the galls are 
moist (whether young or old) they are as soft as rubber. 
When dried, they quickly become as hard to cut with a knife 
or drill as tho they were made of so much compacted, ground 
glass. In order to mount such specimens on insect pins for 
preservation in our collections we soak the galls in water for 
a few hours, or place them out-of-doors in a damp location 
for a few days, after which they are readily penetrated by 
the pins. 
In addition to the six varieties now known in this species, 
there are probably two or three additional varieties still to 
be described from California, but probably none to be expected 
elsewhere in this country. 
Cynips echinus variety douglasii 
agamic form douglasii (Ashmead) 
Figures 23, 154-159, 175 
Holcaspis douglasii Ashmead, 1896, Proc. U.S. Nat. Mus. 19: 127. Cock- 
erell, 1900, Ent. Stud. 1: 9. Thompson, 1915, Amer. Ins. Galls: 10, 
39. 
Dryophanta Douglasi Mayr, 1902, Verh. zoo.-bot. Ges. Wien 52: 290. 
Holcaspis Douglasi Dalla Torre and Kieffer, 1902, Gen. Ins. Hymen. 
Cynip.: 53. 
