356 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxi. 



phia and Westmoreland counties, Pennsylvania; Washington City; 

 Gooroia; Chokoloskee, Florida; and from Dallas, Texas; southern 

 Illinois; Virginia; Nevada and California. Two dates of capture are 

 September 80, 1902, at Belle Plain, New Jersey, and September 26, 

 1904, at Paris, Texas. 



There has been some question as to the identity of C. macrocej)hfilum 

 Fox with C. aztecum Saussure. The two mandibular teeth of the 

 latter as compared with the teeth of the former would lead to the 

 belief that in O. macroceplialuni the lateral tooth is the result of the 

 fusion of two placing it in the three-toothed group; the relative length 

 of the first segment of the filament as compared with the seventh or 

 eighth is ver}^ different in the two, and though these differences are 

 sexual and normal in Priononyx the}'^ do not occur as such in Isodontia. 

 As Doctor Kohl has seen and studied Saussure's type of aztecum 1 sent 

 authoritative specimens of macroccpJud urn to him for examination and 

 he writes as follows: " Meine azteea umfasst die Is. macrocephala von 

 Fox, welche dunkelhaarig ist und gleichmilssig gebriiunte Flugel zeigt, 

 und auch Hire /v. macrocephala var. ctnerea mit greisen Haaren und 

 Fliigeln die an der Vorderhiilfte sehr dunkel hinten aber aufgehellt 

 sind." This would seem to conclusivelv place iiiacroceplialum as a 

 synonym of aztecum. 



CHLORION (ISODONTIA) AZTECUM CINEREUM (H. Fernald). 

 Isodontia macrocephala var. cinerea H. Fekxalu, Can. Ent., XXXV, 1903, p. 271. 



Types: Four females, now located one each in the collections of the 

 U. S. National Museum in Washington (Type, Cat. No. 6932, U.S.N.M.), 

 American Entomological Society in Philadelphia, Dr. W. H. Ashmead 

 in Washington City, and the Massachusetts Agricultural College, 

 Amherst, Massachusetts. 



This subspecies differs from the typical form in its clothing, which 

 is more abundant and dirty white in color. The hairs cover the thorax 

 thickly, particularly on the dorsum of the median segment. The sil- 

 very white pubescence, of whicii there is generally only a trace, is also 

 more developed here, usuall}- being very noticeable on the clypeus and 

 frons up to the level of the insertion of the antennre. Generally, too, 

 the wings are less fuliginous and the violet reflection is correspond- 

 ingly weaker. The size of the individuals averages about the same as 

 in the typical members of the species. 



The specimens of this subspecies seen were captured at Coluni])ia, 

 South Carolina; Enterprise and Indian River, Florida; Georgia; and 

 Dallas, Texas. 



CHLORION (ISODONTIA) AURIPES, new name. 



\\Sphe.v tihialin hErELETiTiR, Hist. Nat. Ins. Hym., Ill, 1845, p. 339. 

 Sphex tibialis Packard, (iuide to Study of Ins., 2d ed., 1870, p. 168. 

 Sphex tibialis CREHsoii, Trans. Am. Ent. See, IV, 1872, p. 211. 



