No. 2368. AMERICAN SUBTERRANEAN CALLS ON OAK— WELD. 233 



basal, very short brown pubescent, ciliate only on hind margin of 

 hind wing. Abdomen longer than thorax, longer than high, later- 

 ally compressed, smooth and shining, second segment occupying 

 about two-thirds and with a tuft of hairs on each side at base. Ven- 

 tral spine tapering, about twice as long as broad, ovipositor when 

 dissected out nearly one and one-half times as long as antenna, 

 ovarian eggs well developed. Using width of head as a base, the 

 length of mesonotum ratio is 1.3; antenna, 2.1; ovipositor, 3.1; 

 wing, 3.3. 



Length of 9 pinned specimens, 2.5-3.1 mm. Average, 2.9 mm. 



Type.— Cat. No. 22581, U. S. N. M. Type and 5 paratypes. 



Host. — Quercus gainbelii Nuttall. 



Gall. — Similar to those of Compsodryoxenus tenuis Weld. The 

 insects gnaw individual exit holes through the brown bark, which 

 after a year or two becomes cracked and rough. 



Type locality. — Las Vegas, New Mexico. Galls were collected in a 

 patch of runner oak of an unknown species on April 4, 1918. They 

 then contained adults, and living flies were cut out which bear Hop- 

 kins U. S. No. 15601 dl . On April 19 similar galls were collected at 

 Flagstaff, Arizona, on Quercus gambelii. They contained similar 

 adults, which issued April 10-16 and bear Hopkins U. S. No. 15601 d . 



31. BASSETTIA FLORIDANA Ashmead. 



Plate 34, fig. 25. 



Bassettia floridana Ashmead, Trans. Amer. Ent. Soc, vol. 14, 1887, p. 147. — 

 Cresson Syn. Amer. Hym., 1887, p. 310.— Dalla Torre, Cat. Hym., vol. 2, 

 1893, p. 117. — Dalla Torre and Kiepfer, Wytsman Gen. Ins. Hym. Cynipi- 

 dae, 1902, p. 72, No. 1; Das Tierreich, Lief. 24, 1910, p. 648.— Thompson, Cat. 

 Amer. Ins. Galls, 1915, p. 36. 



This species was described from four females captured at large in 

 Florida. In cutting open galls of Compsodryoxenus numilis Weld 

 (p. 236) some specimens were found with much longer larval cells 

 than is characteristic of that species, and the flies ran to the genus 

 Bassettia. They agree very well with the two types of B. floridana 

 Ashmead in the United States National Museum (one pinned and one 

 in balsam), except that in these fresh specimens the abdomen is longer 

 than head and thorax together, while in the dry pinned type it equals 

 thorax. The eight fresh flies measure 2.75-2.95 mm. The type 

 floridana measures 2.6 mm. As the original description of floridana 

 was brief, some further notes from the type specimens are here added 

 and the associated gall described for the first time. 



Host. — Quercus chapmani Sargent. 



Gall. — Spindle-shaped enlargements at base of current year's shoots 

 occurring in patches of runner oak in fall. (Plate 34, fig, 25.) In ex- 

 ternal appearance they can not be separated from galls of Compsodry- 



