March, '05] ENTOMOLOGICAL NEWS. 89 



Entomological Literature. 



Coloration in Polistes forms the subject of quite a lengthy paper by 

 Miss Wilhelmine M. Enteman recently issued by the Carnegie Institution 

 of Washington, as publication No. 19. All Hymenopterists will welcome 

 the work as it throws considerable light on the taxonomy and variation of 

 this interesting and extensive genus of wasps. The matter of coloration 

 is taken up first in its relation to the ontogeny of the wasp. The develop- 

 ment of the colors was observed to pass through much the same stages 

 as those described by Mayer for butterflies. In the case of Polistes the 

 hypodermal pigment forms the lighter shades of drab and yellow mark- 

 ings where it has not been overshadowed by the darker cuticular pig- 

 ment deposited in the chitin. A chemical examination of the pigment 

 reveals the fact that it shows a great similarity in many of its reactions to 

 the group of benzole derivatives known as the " azo " dyes. The color 

 variation of large series of wasps has been examined and compared by 

 means of statistical methods, and it is pointed out that variation in mem- 

 bers of the genus is continuous, all of the widely different types of colora- 

 tion shading into one another through insensible gradations. A correla- 

 tion in color between the different parts of the body is shown and its 

 relation worked out in detail. 



One of the most interesting features is the relation which is to be 

 observed between variation and enviroment. The development of pig- 

 ment in the wasps aside from hereditary influences seems to depend in 

 great measure on temperature and humility. Thus the desert species of 

 portions of Arizona and the southwest tend to be pale without the darker 

 and warmer tones of brown and black shown in northern forms. This 

 tendency toward melanism is evinced most strongly in the colder humid 

 portions of the coastal region of both North America and Eurasia. A 

 close relation between the forms inhabiting the eastern coast of Asia and 

 of North America is pointed out and a map of the world showing distribu- 

 tion presented. 



There is only one bad feature to mar the general excellence of the 

 work, and that is the presence of a couple of very badly executed plates. 

 Plate IV shows a number of inaccuracies in structure and wing venation 

 and the figure purporting to be Polistes ruhi^inosiis would scarcely be 

 mistaken for that species by any one familiar with the latter. Text 

 figure i is also inaccurately lettered. 



No attempt at limiting species is made although a number of the points 

 worked out will be of aid to the future entomologist who may undertake 

 this difficult task. C. T. B. 



JERKY, a good friend of mine, has started in to form a collection of the 

 fleas of the world. Do not send exchange lists or specimens unless asknl 

 for. Hardly necessary to say, that Jerry is the name of my dog. Pnii.il 1 

 LAURENT. 



