1926] Phenology of Inquiline and Nest-making Bees 
117 
seen the inquiline enter the burrows. Oligotropus campanula, 
June 25-Sept. 14, is probably infested by C. modesta, June 25- 
Aug. 28, both small species. The flight of C. texana, June 25- 
Aug. 14, and C. germana, June 25-Sept. 3, are covered by the 
flight of Megachile generosa, June 11-Sept. 28, M. sexdentata, 
June 14-Sept. 10, and M. petulans, June 17-Sept. 20. According 
to Shuckard (7) Codioxys infests Megachilini with modified front 
tarsi. There are not as many inquilines as would be expected 
otherwise. 
Osmiince and Stelidini . — The Osmiinse fly 211 days, Mar. 21- 
Oct. 18, with a maximum of 75 per cent June 16, 90 per cent 
flying in June. May 21-25, 28 and June 6-11, 70 per cent are 
flying. The Stelidini fly 163 days, May 9-Oct. 18, all together 
May 7-14. 
Alcidamea simplex, 85 days, May 3-July 26, and Microstelis 
lateralis, 43 days, May 9- June 20, are host and inquiline (Crawford 
8, 5)., Neotrypetes carinatus, 144 days, May 28-Oct. 18, and 
produdus, 138 days, June 3-Oct. 28, the females mixed and 
counted for both species, are evidently infested by Stelidium 
trypetinum, 135 days, June 6-Oct. 18. In 6 , 109, produdus should 
be carinatus. 
Bombince and Psithyrus. — Bombus americanorum, Mar. 5- 
Nov., and P. variabilis, Apr. 28-Nov., are host and inquiline, as 
stated by Frison (1). Their time and frequency indicate this. 
Halididce, Sphecodini and Paralidus . — The Halictidse, Mar. 
17-Nov., are probably infested by Sphecodini, Mar. 31-Nov. 
Chloralidus is probably host of Paralidus, both March 15-Nov. 
P. cephalicus, May 9-Oct. 19, was taken at a bank where C. 
zephyrus, Mar. 21-Nov., was nesting. 
I would arrange the Halictidse as follows: Halictinae, wing 
veins not enfeebled; Halictini: Halictus, etc.; Sphecodini: Sphe- 
codes, etc.; Lasioglossinse, outer veins enfeebled; Lasioglossini : 
Curtisapis, Evylseus; Chloralictini : Chloralictus, Dialictus, Pa- 
ralictus. The last is an offshoot from Chloralictus. The Spheco- 
dini were derived from Halictini, not from the forms with outer 
veins enfeebled. 
Andrenidce and Nomadidce . — The Andrenidse fly 227 days, 
March 17-Oct. 30, have a maximum of 68.8 per cent May 11-13, 
