No. 2368. AMERICAN SUBTERRANEAN GALLS ON OAK— WELD. 193 



On Q. breviloba 4. Disholcaspis brevinota Weld, p. 197. 



On Q. gambelii. Larger and more irregular than those of globulus. 



2. Disholcaspis lacuna Weld, p. 195. 

 Bullet galls of harder texture and no separable inner cell — 

 Blunt, reddish, 7-8 mm. in diameter. Q. gambelii. 



1. Disholcaspis acetabula Weld, p. 194. 



Similar on Q. grisea, toumeyi, reticulata and probably other oaks in 



the Rocky Mountain region .. Probably No. 1. See note, p. 195. 



TEUE STEM GALLS ERRONEOUSLY DESCRIBED AS ROOT GALLS. P0LYTHALAM0US. 



Globose, hard, densely granular inside. On Q. reticulata, arizonica, oblongi/olia, 

 toumeyi 15. Andricus rhizoxenus ( Ashmead) , p. 211. 



Irregularly oblong, grayish, brown, and very hard and granular inside. Large 

 Unknown oak. Mexico 1G. Andricus championi Ashmead, p. 212. 



CAPTURED SPECIES REPORTED IN LITERATURE AS FROM UNKNOWN GALLS ON ROOTS OF OAK. 



Biorhiza nigra Fitch. See Ashmead, Trans. Amer. Ent. Soc, vol. 9, Proc, p. 24, 

 and Riley, Science, new ser., vol. 1, p. 462. Later Ashmead placed this species in 

 the genus Xystoteras. 

 Philonix fu hico His Fitch . 

 Philonix nigricollis Fitch. 



All three species were captured on snow. It is more than probable that they 

 are not from root galls at all, but from leaf galls, as all the species of Xystoteras 

 and Philonix whose galls are known come from leaf galls, which drop to the 

 ground in late autumn. In several cases the adults are known to emerge in 

 November or December after snow has begun to fly. They are very resistant 

 to cold, are long lived, and oviposit in buds on pleasant days in winter. 



Genus DISHOLCASPIS Dalla Torre and Kieffer. 



KEY TO THE SPECIES OF DISHOLCASPIS HEREIN MENTIONED. 



1. Scutellum not rugose on disk, but lacunose, i. e., with shallow contiguous pits 



in each of which is a setigerous puncture (best seen in balsam). Rocky Mount- 

 ain species 2 



Scutellum rugose, with setigerous punctures 3 



2. Scutellum with shallow median groove on disk, head somewhat angular on sides, 



malar space striate, face with only a narrow dark transverse band across base of 



antennae, cubitus distinct acetabula Weld, p. 194. 



Scutellum without median groove, sides of head rounded, malar space not striate, 

 whole face infuscated , cubitus and apex of areolet very pale . . lacuna Weld, p. 195. 



3. Areolet reaching one-fourth way to basal and cubitus nearly reaching basal, the 



gap being less than length of areolet globosa Weld, p. 196. 



Areolet reaching only one-sixth to one-fifth way to basal, gap between basal and 

 proximal end of cubitus greater than length of areolet 4 



4. Mesoscutum distinctly broader than long (length about three-fourths width). 



brevinota Weld, p. 197. 

 Mesoscutum length and breadth subequal or else longer than broad 5 



5. Ocellar area black, pronotum infuscated on sides, mesopleura with an oblique 



black line across, mesoscutum infuscated between parapsides clear to scutellum, 

 second abdominal tergite with broad dorsal infuscation, but red on sides. 



globulus (Fitch). 



6. Ocellar area not infuscated, no black line across sides of pronotum or across meso- 



pleura, the infuscation between parapsides stops abruptly two-thirds way back 

 to scutellum, second abdominal tergite with narrow dorsal black stripe and 



black on hind margin, sides red terrestris Weld, p. 198. 



27177— 21— Proc.N.M.vol.59 13 



