THE TUMBLING FLOWER BEETLES. 



1317 



2436 (7796). Mordellistena arida Lee., Proc. Phil. Acad. Nat. Sci., XIV. 

 1862, 48. 



Larger and slightly darker than lutea. Ridges of tibia and tarsi Longer 

 and stager than there, those of the first Joint of hind tars, much more 

 oblique. Length 3.5-4 mm. 



Lake Porter and Tippecanoe counties; scarce. June 27-July 

 21 The' specimens from Lake and Porter counties were taken from 

 the flowers of the prickly pear cactus, Opuntia rafinesqim Engelm. 

 Both LeConte and Smith state that 

 arida has but two ridges on first joint, 

 but all the specimens at hand have three. 

 Dr. Smith pronounces them arida, stat- 

 ing that "the difference in the ridges is 

 within the range of variation. ' ' This is, 

 of course true, but how about the keys, 

 Avhich are based on an unvarying num- 

 ber of ridges? 



GROUP C. Fig 577 0j Hind tibia and tarsus of 



+1 x-i- Ka.*rr two MordeUistemtrifascmta; b, elytron of same; 



In this group the tibiae bear two c> elytron of M , Kmbfl fe. (After Smth.) 

 equal oblique parallel ridges on the ' , , 



outer face. (Fig. 577, a.) The following species have been taken 

 or should occur in Indiana : 



KEY TO INDIANA SPECIES OF GROUP C. 



a First joint of hind tarsi with two oblique ridges. 



h Second joint of hind tarsi with but one oblique ridge. 



, Elytra black with two transverse yellow bands, the front one part- 

 X ^interrupted at suture by a prolongation of the black band at. 



a Body black; thorax black with basal margin and sides dull yel- 



U. DUUj uicxv. , TRIFASCIATA. 

 low. , -, ,. , 



M . Body yellow ; thorax yeHow with a faint fuscous *ud ^ 



cc Elytra without transverse yellow bands. 

 e Color above wholly or in great part pale. 



, TUorax with front angles and a large spot ou^rfev^ 

 black. 



ff Thorax and elytra wholly pale clay yellow. 2440. vapida. 

 ee. Color above wholly or in great part black or piceous. 

 a Elytra with a reddish-yellow oval humeral spot. 



• /- 2441. BIPLAGTATA. 



an Elvtra without distinct humeral spot. 



' n Head, thorax and legs, except the hind femora, reddish-yel- 



DIMIDIATA. 



low. 



