AMERICAN HYMENOPTERA. 297 



24. s Mill il hi creusa Cresson (37). 



Plate IV, fig. 12; petiole of medea. 



Two specimens of the variety medea Cress, were taken at Fedor, 

 Texas, May (Birkmau), one with the cephalic hairs black, the other 

 bright orange above. 



Arizona (Westcott) ; Las Cruces, Las Vegas, Mesilla Lark, While 

 Mountains (6300 feet), New Mexico (Cockered). 



One of Mr. Cockerell's specimens was found in combat with 

 Microbembex monodonta. In view of the similar struggles between 

 the bee Halietus and Mutilla canadensis, which we have observed, 

 it may be surmised that this species (var. medea) is a parasite of the 

 Bembecid. 



25. M ul ilia iegina Cresson (39). 



Plate IV, fig. 13; petiole. 

 Rather common, ranging in size from nine to eighteen mm. 

 Fedor, Austin, Columbus, Texas. (May to September.) New 

 Mexico (M. C Z.). 



26. Mutilla qiiadi'iguttata Say (42). 



Plate IV, tig. 14 ; petiole of elect ra. 



Not rare, occurring as the typical -form and the variety electra 

 Blake, at Fedor, Austin and Cuero, Texas. (May to October.) 



Although inconstant as to color, this species has produced no 

 variety as aberrant as a specimen from Fedor. In this individual 

 the thorax is over one half longer than usual, not constricted above 

 the middle legs nor rounded posteriorly, but is broadly ovate, with 

 the sides subparallel. Otherwise the sculpture and color agree per- 

 fectly with typical quadriguttata. 



27. Mutilla ferrugata Fabr. (43 and 66). 



Mntilla ferrugata Fabr. <p . 

 Mutilla fenestrata Lep. % . 

 Mntilla Lepeletierii Fox. 



Plate IV, fig. 15; petiole of female. 



Both the males and females are very common. 



Woods Hole, Mass. ; Colebrook, Conn. ; New Hampshire; Mary- 

 land ; Pennsylvania; Illinois; Nebraska; Kansas; Austin, Texas ; 

 Arizona. 



It is quite doubtful if castor Blake, macra Cresson, and agenor 

 Fox are valid species. If they are not forms of ferrugata the struc- 



TRANS. AM. ENT. SOC, XXIX. (38) OCTOBER, 1903 



