ART. ly. GALLFLIES OF THE FAMILY GYXLPIDAE WELD. i 



of these cells at various points around its periphery and the flies 

 make separate holes to the exterior through the acorn cup. Occurs 

 in late summer and autumn in acorns of current season's crop. 



At the time the species was first described it was associated with 

 a stony mass of galls more or less filling the interior of the acorn, the 

 work of a new species described in the present paper as CalUrhytis 

 miller I Weld, page 11. Although 

 this stony gall and the eldoraden- 

 sis flies bore the same Koebele 

 number, Beutenmueller suggested 

 that the two might have nothing 

 to do with each other. C. miller'/ p,Q i._biorhitza eldoradensis (Beu 

 produces a confluent mass of cells tbnmukllbr). cells in acorns of 



. ^, . , . , • 1 1 Tifi. 1 WISI.IZKNt (TWO OX LEFT) AND AGEI- 



m the interior whicii can be liitea ^qlia (on right), x i. 



out intact; eldorademsh produces 



separate cells in base of acorn not separable from the wall. The type 



galls of eldoradensis consist of one acorn of each kind. The writer 



has seen both species working in the same acorn, hut the two types 



of work are easily recognized. 



Habitat.— Acovns of agrifolnt affected by this species have been 

 seen by the writer at Newhall, Piru, Fillmore, in Ojai Valley, Monte- 

 cito, Santa Barbara, Paraiso Springs, Los Gatos. Berkeley, and St, 

 Helena. California. Tliose of wisUzem in San Gabriel River canyon 

 above Azusa. at Santa Margarita, Los Gatos. and Bagby. California. 



Genus CALLIRHYTIS Foerster. 



All the species of this genus reared from acorn galls are, so far 

 as now known, characterized bv having remarkably hyaline winds due 

 to the fact that the pubesence on the surface is either very short 

 or almost wanting. The fore wing of the female also lacks the nor- 

 mal cilia on the margin, the fore wings of the males having the 

 margin ciliate but the surface short pubescence like the female. The 

 same is true of most species of this genus reared from root galls. All 

 the oak flower galls (except two made by species in other genera), 

 a number of twig swellings, a few midrib swellings, a hard leaf 

 parenchyma gall and one bud gall also yield flies which go in this 

 same section of the genus Callirhi/tis, so it seems best not to limit the 

 discussion to the acorn gall species alone but to treat this section of 

 the genus as a whole in order to bring together in one place all 

 these related species and get some possible hints on life-history prob- 

 lems. Those flies which come from leaf parenchyma and midrib 

 swellings have an unusually long ovipositor and they may oviposit 

 in acorns and produce an acorn stone gall for the alternating genera- 

 tion. Certain species (sexual) from big wooly flower galls also have a 

 long ovipositor, but not so long as those mentioned above. One of 

 20107— 22— Proc. N. M. vol. 61 26 



