68 COLORATION IN POLISTES. 



courtesy of Mr. Fox, and on the distribution of species as given in the 

 latter's paper (8). Mr. Fox adheres in the main to De Saussure's 

 classification, but he has created several species in addition to those 

 given by De Saussure. 



From this collection and Mr. Fox's account of the genus, it becomes 

 evident that by far the greatest number of species approach the carolinus 

 and ihQ pallipes types in their coloration. These types are also most 

 widespread in their distribution, and so far as the peculiarities of habitat 

 can be made out, the carolinus type is characteristic for the tropical 

 zone, the pallipcs for the temperate zone. The latter also passes by many 

 transitions into the canadensis type ; but we find nowhere the extreme 

 development either in size or coloration represented in such members 

 of the rubiginosjis group as rubiginosus, texanus, and JIavus. Neither 

 are the xanthic forms of aicrifer and carnifex to be found here. This 

 is interesting when we reflect that we do not have in the region from 

 which the Polistes were collected any of the extreme climatic condi- 

 tions to which these developments of Polistes seem to correspond. The 

 most suggestive species among these is P. versicolor, occurring widely 

 distributed from Cayenne in the north to Chapada on the south. It 

 appears to be a form transitional between P. aurifer and P. carolimis, 

 and may be regarded as an aurifer in which the yellow is reduced, the 

 usually black areas represented m the main by red-brown, while the 

 black is confined to the ventral side of the thorax, the metathorax, 

 and a triangular area on the second abdominal segment. The loo 

 specimens in the H. H. Smith collection were very variable in the 

 depth of red-brown, the amount of black, and the size and distinctness 

 of the yellow markings, and altogether the species presents a plasticity 

 which might be molded either into the red carolimis of moist, tropical 

 Florida, or into the yellow azirifer of the dry region of southwestern 

 United States. These relations will be considered further in connec- 

 tion with the laws of color differentiation in the genus. 



Distribution in Africa. 



This continent falls into two divisions, northern and southern. The 

 former, including the Barbary States and Egypt, is the home of P. gal- 

 licus, which corresponds to P. auHfer of our country. The latter sub- 

 division, possessing in general uniform climatic conditions, approaches 

 South America in its representation of species. The pallipes type occurs 

 in tropical Africa and at the Cape of Good Hope. The caroliyins type 

 occurs in Senegambia and meridional Africa, and evidently merges 

 into \h& pallipes type ; but since the data for this continent are slight, 

 it is hardly profitable to consider the differentiation here in further 



