June-Sept., 1919.] TlMBERLAKE: HlPPODAMIA. 165 



Glacialis group, ^deagus much thickened throughout, generally 

 bent nearly double upon itself, the dorsal, subapical flaps strongly 

 chitinized except at apex, and undergoing various modifications in 

 shape, but never exactly as described in the preceding groups ; lateral 

 lobes of theca slender; the posterior lobe of theca rather large, broad 

 and considerably deeper than in the convergent group, its apex with 

 an obliquely inclined portion limited by a strongly developed trans- 

 verse keel, which is either straight or deeply emarginate. 



13-punctata Group. 



1. Hippodamia tibialis (Say). 



Coccinella tibialis Say, Journ. Acad. Nat. Sci. Philadelphia, Vol. 4, p. 94, 1824. 

 Hippodamia 13-punctata of American writers, not Linne. 



This is the only species of the group in North America and 

 although very closely allied to 13-punctata (Linne) of Europe it 

 seems to be sufficiently distinct. In 13-punctata from Spandau, 

 Prussia (Th. Pergande), the posterior lobe of the theca is abruptly 

 widened close to the apex, its sides in dorsal view meet in a right 

 angle at the apex and are slightly emarginate. In tibialis the pos- 

 terior lobe is only slightly and gradually widened near the apex, its 

 sides are straight and meet more acutely at the apex. Strange as it 

 may seem at first thought, a male from Gifu, Japan (Y. Nava), 

 exhibits the tibialis character slightly more accentuated even than in 

 North American specimens. The writer has studied the genitalia of 

 tibialis from St. Anthony Park, Minnesota (R. A. Vickery) ; Madi- 

 son*, South Dakota (R. A. Vickery) ; Tower City, North Dakota 

 (Miriam W. Reeves) and from Taylorsville, Utah (P. H. 

 Timberlake). 



Parenthesis Group. 



2. Hippodamia parenthesis (Say). 



Coccinella parenthesis Say, Journ. Acad. Nat. Sci. Philadelphia, Vol. 4, p. 93> 



1824. 

 Coccinella tridens Kirby, Fauna borealis-Americana, pt. 4, p. 229, 1837. 



In this species the posterior lobe of the theca is not compressed 

 beneath and its apex is produced into a short, barbed point. The 

 genitalia have been examined in specimens from West Springfield, 

 Massachusetts (H. E. Smith) ; Hagerstown, Maryland (J. A. 

 Hyslop) ; Tower City, North Dakota (Miriam W. Reeves) ; Fort 



