ART. 18. KOTES ON CYNIPID WASPS WELD. 21 



on Bine Hill, Massachusetts; at Miller, Indiana ; in Illinois at Evans- 

 ton, Fort Sheridan, and Pales Park; at Ironton, Missouri; and at 

 Palestine, Boerne, Austin, and Kerrville, Texas. They occur on 

 Quercus rubra, coccinea., falcata, llicifoUa, myrtifoKa^ fumila^ cate- 

 shaei, and texcma. besides the oak from which it was described, 

 hrevifolia. 



The young galls may be found forming from late May to early 

 June, secreting honeydew from a gland at apex and at this stage 

 containing a thick translucent nutritive layer inside, with a scarcely 

 discernable larval cavity in center. On June 16, 1917, a cluster of 

 dcA'eloping galls was found at Fort Sheridan on I'ti'bra and watched 

 at intervals during the summer. "Wlien visited a month later many 

 of the galls were found to be plump and green, with a nipple at 

 apex and many cells inside and they continued to enlarge and finally 

 become woody and covered on outside with normal brown bark and 

 remained on the tree all winter. They became the characteristic galls 

 known in literature as Andncus davisi Beutenmueller, and from them 

 only guest flies are reared. The types of davisi seen by the writer 

 in six different collections are all guest flies of the genus Synergiis. 

 When attached by inquillines the galls, instead of dropping to the 

 ground, keep on growing and remain on tree. 



In the Bulletin of the American Museum of Natural History (vol. 

 42, 1920, p. 295), Doctor Kinsey, working with museum specimens 

 only without field observations on the growing galls, recognizes that 

 the characteristic galls of davisi yield only a Synergus, but he is in 

 error in thinking that they are derived from Callirhytis punctata 

 (Bassett). In favorable specimens one can often find on the summit 

 of the davisi galls a trace of the nipple and ribbed surface of the 

 normal gemmaria gall. In a footnote he admits the possibility of his 

 error, but does not say from what they are derived. 



True parasites by killing the maker may stunt the growth of a gall 

 and cause a characteristic appearance, and guest flies may also 

 modify it. Cecidologists when describing galls should be sure they 

 are describing a normal structure, and one can not always be sure 

 of this from single specimens. They may be sure it is normal if 

 they rear the maker, or, failing in this, find the gall in numbers and 

 especially season after season. 



CALLIRHYTIS MEDULLAE (Ashmead). 



Cynips )iieduU(ie Ashmead, Trans. Amer. Ent. Soc, vol. 12, 1885, Proc, p. 8. 

 The two type females in the United States National Museum have 

 the head not distinctly broader than thorax and simple claws and 

 they belong in Callirhytis. As the fore wings have very short pubes- 

 cence, the margin without cilia, and the venation pale, the sj^ecies 

 20107— 22— Proc. N. U. vol. 61 25 



