June-Sept., 1919.] TlMBERLAKE: HlPPODAMIA. 171 



1. The transverse keel near apex of the posterior lobe of theca deeply emar- 



ginate 2 



The transverse keel not emarginate ; the posterior lobe of theca rather thick 

 dorsoventrally, more nearly terete than in the other groups, tapering 

 gradually from the base to the keel and then more abruptly to the acute 

 apex ; its dorsal surface rather flat, the apical portion sloping downward 

 and backward from the margin of the keel 10. 5-signata (Kirby). 



2. Emargination of the transverse keel rounded 3 



Emargination of the transverse keel acutely angled ; the posterior lobe of 



theca of the same general shape as in 5-signata, but as seen from above 

 the lateral margins are slightly emarginately rounded and somewhat 

 expanded at the ends of the keel ; its dorsal surface longitudinally 

 grooved, the area enclosed within the emargination of the keel in the 

 form of a rather deep, rounded depression ; the apical portion obliquely 

 inclined from the margin of the keel, the apex of the emargination 

 reaching nearly two-thirds of the distance to the apex of the lobe. 



11. extensa Mulsant. 



3. Posterior lobe of theca much as in 5-signata, but a little wider, more de- 



pressed, less tapering toward the apex and wider at the transverse keel ; 

 its dorsal surface slightly longitudinally grooved in the middle on the 

 basal part, the area enclosed by the keel somewhat obliquely inclined, 

 but hardly concave ; the apical portion obliquely inclined from the mar- 

 gin of the keel, the apex of the emargination reaching about one-half 

 of the distance to the apex of the lobe ; dorsal flaps of aedeagus linear, 

 rounded and membranous at apex, but heavily chitinized at base, the 

 apical part of aedeagus nearly three times as long as the flaps. 



12. glacialis (Fabricius). 

 Posterior lobe of theca as in glacialis except that the keel is a little more 

 deeply and more broadly rounded emarginate, the lateral margins as seen 

 from above nearly parallel as far as the obliquely inclined apical part ; 

 dorsal flaps of aedeagus chitinized throughout, a little broader toward 

 the base, and somewhat emarginate on the inner side just before the 

 apex, the apical part of aedeagus about twice as long as the flaps. 



13. Hippodamia sp. indet. 

 10. Hippodamia quinquesignata (Kirby). 



Coccinella 5-signata Kirby, Fauna borealis-Americana, pt. 4, p. 230, pi. 7, fig. 

 1, 1837. 



This species is extremely variable and has become segregated into 

 numerous geographical races of which the following have been 

 studied: 



Hippodamia coccinea Casey, Canad. Entom., vol. 40, p. 395, 1908. 

 Hippodamia vernix Casey, Journ. N. Y. Entom. Soc, vol. 7, p. 79, 



1899. 



