REVISION OF ELEODITNI BLAISDELL. 37 



Morphologically the pronotuni is widest at the middle in both 

 sexes; but in the female there is a stronger lateral declivity, with a 

 varying amount of lateral compression behind the middle to make 

 the sides appear more or less straight from middle to base; con- 

 versely, there is less deflexion anterior to the middle so that indi- 

 viduals of the same species and sex may be more or less strongly 

 arcuate before the middle. In hir/neralis there is less deflexion than 

 in any other species of Melaneleodes, the marginal bead being nearly 

 always visible in the typical form Avhen the pronotum is viewed 

 vertically from above. 



The degree to which the angles are deflexed also gives a varying 

 aspect to the pronotum. By a careful study of the different species 

 in this respect the student will observe that really the pronotum is 

 broadly, evenly, and rather strongly arcuate in the anterior two- 

 thirds and thence to base more or less feebly sinuate. 



The above remarks apply to what I call a normal subgeneric varia- 

 bility. 



Certain fortuitous deviations do occur which are not always easy 

 to explain. The unique s])ecimen described by me a number of years 

 ago as interriipta is a case in point where environment has given evi- 

 dence of hiHMS natnra'. 



The legs vary considerably in regard to length and stoutness of the 

 different segments; sometimes these variations depend upon certain 

 inherent traits of ancestral or developmental origin, constituting an 

 abnormal condition in the relative proportions of the appendages 

 and body. These evasive factors may affect any appendage or 

 somitic part, and a student must bear these data in mind Avhen deal- 

 ing with the diagnosis of species or referring specimens to their place 

 in the sche?na taxonomicuin. 



On account of this variability within specific limits, I have given 

 attention to the general relative j^roportions of parts under each 

 species. I have been induced to do this from the extraordinary large 

 series of specimens at hand. 



Disti'ihution. — The species of Melaneleodes inhabit the follow- 

 ing States and countries: Texas, New Mexico, Arizona, Colorado, 

 Nebraska, Kansas, Oklahoma, Montana, South Dakota. California, 

 Lower California, Washington, Oregon, Idaho, Nevada, ITtah, Indian 

 Territory, British x\merica (Medicine Hat, Riley) (?), Mexico (see 

 hiimeralis and quadricoJIis), Iowa, Wyoming. 



Distributed through 19 States out of the 23 west of the Mississippi 

 River. I have no record of specimens from Missouri, Arkansas, 

 Minnesota, and Louisiana. I expect to hear of their occurrence in 

 one or more of those regions. 



