140 Psyche [August 



Megacephala Cresson 1878. Texas {Heiligbrodt). Tab. 1. Male 



of texana. 

 Melanostoma Swenk and Cockerell 1907. Glen, Sioux Co., 



Nebraska (P. R. Jones). Visits Gutierrezia. 

 Mellina Cockerell 1900. Phoenix, Arizona {Cockerell). Tab. 5. 



Visits Heterotheca. 

 Mentzeliae Cockerell 1896. Santa F6, New Mexico (Cockerell). 



Tab. 1, 2, 4. Visits Nuttallia. 

 Mentzeliarum Cockerell 1897. Riley's Ranch, Organ Mts., 



New Mexico {Cockerell). Tab. 2, 4. Visits Nuttallia. 

 Mentzeliarum lauta Cockerell 1905. Near Tularosa, New 



Mexico {E. 0. Wooton). Visits Nuttallia. 

 Mexicanorum Cockerell 1896. Mexico. Tab. 1. Peculiar for 



its yellow postscutellum. 

 Monardae Viereck 1904. Riverton, New Jersey {Viereck). 



Visits Monarda. 

 Nebrascensis Swenk and Cockerell 1907. Neligh, Nebraska 



{M. Cary). Visits Helianthus. 

 Nevadensis Cockerell 1896. Nevada. Tab. 1. 

 Nitidella Cockerell 1895. Las Cruces, New Mexico {Cockerell). 



Tab. 1, 2. Visits Isocoma. 

 Novaeangliae Viereck 1907. Poquonock, Ct. {Viereck). Flies in 



June and July. Also in Massachusetts. 

 Nuda Cockerell 1896. New Mexico. Tab. 1, 2. Resembles 



P. phymatce, but much larger. 

 Numerata Cockerell 1895. Las Cruces, New Mexico {Cockerell). 



Tab. 1, 2. Visits Salix in May. 

 Obscurata Cresson 1878. Georgia. Tab. 1. Visits Hydrocotyle. 



Also occurs in Florida. 

 Octomaculata Say 1824. United States. Tab. 1. Visits Covi- 



positcp; Illinois to Atlantic coast. 

 Pallid ior Cockerell 1896. Albuquerque, New Mexico {Cocker- 

 ell). Tab. 1, 2. Very near to P. mentzeliw. Visits Nuttallia. 

 Pallidior pulchrior Cockerell 1896. Albuquerque, New Mexico 



{Cockerell). Tab. 1, 2. Cheeks of male spined. 

 Pallidipennis Graenicher 1910. Mouth of Yellow River, Wis- 

 consin {Graenicher) . Group of P. albipennis. 

 Pectidis Cockerell 1896. Las Cruces, New Mexico {Cockerell). 



