DATA OF DISTRIBUTION. 



The species of this genus, like the rest of the Chrysomelidse of North 

 America, show a marked tendency toward the development of groups about 

 some central type. In Lcpthiotaisa this is carried to the extent that all 

 of the species fall into well-marked series not connected by intermediate 

 conditions. Each of these is traced with ease backward into the genus 

 Zygogramma, which is the ancestor of the genus Leptinotarsa. 



The species fall naturally into the following groups : 



Flavopustulata Group. 



Leptinotarsa stali. 



evauesceus. 

 dobrni. 

 beiti. 

 flavopustulata. 



Haldemani Group. 



Leptinotarsa dablbomi. 

 hogei. 

 haldemani. 

 libatrix. 

 violescens. 

 chlorizans. 

 litigiosa. 

 tlascalaua. 



Lacerata Group. 



Leptinotarsa lacerata. 

 beydeni. 

 puncticollis. 

 ruodesta. 

 chalcospila. 



LineaTa Group. 

 Leptinotarsa undecimlineata. 

 diversa. 

 angustovittata. 

 signaticollis. 

 multitseniata. 

 oblongatB. 

 rnelanothorax. 

 rubicunda. 

 intermedia, 

 decemlineata. 

 defecta. 

 juncta. 



Dilecta Group. 

 Leptinotarsa calceata. 



novemlineata. 



dilecta. 



flavitarsus 



nitidicollis. 



obliterata. 



lineolata. 



pudica. 



typographica. 



distinguenda. 



Rueiginosa Group 

 Leptinotarsa rubiginosa. 



Zetterstedti Group. 

 Leptinotarsa zetterstedti. 



The distribution of these groups over North America shows a strong 

 development in numbers and in species in southern Mexico. Only i reaches 

 the northern United States and Canada, 3 reach the southern United States, 

 and 6 northern Mexico, while 30 are found in southern Mexico only, 4 in 

 Guatemala, and 2 as far south as Costa Rica and Panama. 



