408 PROCEEDINGS OF THE ACADEMY OF [April, 



presence or absence of a decided pattern within a species being few. 

 The descriptions have been drawn up to cover as fully as possible the 

 extremes, the measurements in all cases representing these except 

 in a few dimensions where the most extreme specimens of a species 

 examined have an identical measurement. 



The form of the tegmina in the female sex furnishes one of the most 

 Interesting phases of specific divergence in this genus and it proved 

 to be the rock on which a number of species were split off on one side 

 into Loboptera and on the other into Temnoptcryx. It is quite apparent 

 that the form of these appendages is much less important in these 

 species than was formerly supposed to be the case, as species very 

 similar in general appearance, other structures, including genital 

 appendages, and in coloration will differ considerably in teg- 

 minal form, although the form and proportions of these are quite 

 constant within specific limits. Several of the species are difficult 

 to separate in the male sex, while the females are quite easy to dis- 

 tinguish ; in one case the females of two forms do not appear separable 

 while the males are typically easy to distinguish. The greater diver- 

 sity in the females when considered with their pronounced, adaptation 

 for life under stones and bark is in decided contrast to the more gen- 

 eralized structure of the males. 



In the case of two forms it has been found advisable to use a tri- 

 nomial, as sufficient evidence of intergradation exists in the territory 

 where the ranges overlap, to demonstrate beyond a doubt that one is 

 but a geographic form or race of the other. In these instances the 

 trinomial shows close relationship, while a binomial would imply a 

 unit distinction which does not exist. 



As several authors have shown the great amount of variability in 

 the number of complete and incomplete rami of the ulnar vein of the 

 wing within specific limits in a number of genera of the Pseudomopince 

 (Phyllodrominrv of authors), we have not used this character in sep- 

 arating species, contenting ourselves with giving in the specific descrip- 

 tions the ramus extremes of the series examined. 



The range of each species has been carefully mapped from the 

 •specimens and literature and the distribution of each species is given 

 from its particular chart. 



The exact position of Temnopteryx deserke Rehn and Hebard 1 is 

 •doubtful, but as the discovery of the male will probably show its 



1 Proc. Acad. Nat. Sci. Phila., 1909, p. 1 16, fig. 1 . [Johnstone, Valverde County, 

 Texas.] 



