ADALIA. 67 



Genus ADALIA Mulsant. 

 3068. Adalia bipunctata Linnaeus. 



Distribution: Europe and Eastern and Central States. 



Typical pattern: Spots 2-3. Double nature of the band not apparent. 



Form pruni Weise. 



Spots 2+3. Double nature of spot apparent. About 1 per cent at Cold Spring 

 Harbor. 



Var. herbsti Weise. 



Spots 2, 3. I have not yet seen this variety in America, but it may be confidently 

 expected because of the occurrence of form pruni and the probability that 

 when found it has been considered to be the A. frigida var. parvula. 



Var. nibigiriosa Weise. 



Spots 1, 2 - 3. Less than 1 per cent at Cold Spring Harbor. 



The 17 other varieties given by Weise (1879), nearly all of which show 

 greater amounts of pigment, have not yet been recorded from America 

 with the exception of 



Var. quadrimaculata Scopoli=C humeralis Say? 



Elytra black, except for a reddish humeral area and a reddish spot near the suture 

 at -. Widely distributed, but always uncommon. 



a b c d * f 



FIG. 70. Variation in prouotal pattern in A. bipitnctatn. c=mode. 



Subspecies of North America: The lack of all varieties with the excep- 

 tion of pruni, rubiginosa, and quadrimaculata, is typical of North Amer- 

 ica as a whole. While some of the other varieties will be found, they will 

 be great rarities, and one may say that North America is characterized 

 by the general lack of the dark varieties, excepting the quadrimaculata.- 



Burgess (1903) has found the variety quadrimaculata and the typical 

 species to be intergenerating. The heredity was perfectly segregate. The 

 variety quadrimaculata is found in Europe in company with numerous 

 varieties which intergrade toward the typical species and to the almost or 

 wholly melanic variety lugubris. It is singular that with us these other 

 varieties should be absent, leaving only the variety quadrimaculata. It 

 can not be because variety quadrimaculata is a position of much greater 

 organic stability, because in Germany (Schroeder, 1901) it is greatly out- 

 numbered by the allied variety sexpustulata, which is less melanic. It 

 justifies the view that at least some of these varieties are not merely 

 ontogenetic in origin or fluctuations, but true varieties representing 

 inheritable positions of organic stability. 



