60 north american blattidae 



The Group Ischnopterites 



The majorlt}^ of the species of this group are less delicate in 

 structure than those of the Blattellites. The tegmina have their 

 discoidal sectors weakly radiating or simply longitudinal, not longi- 

 tudinal and in part springing at a sharp angle from the ulnar vein 

 near the apex of the anal field, or oblique to the discoidal vein. The 

 wings have the ulnar vein with proximal rami incomplete and dis- 

 tal rami complete, reaching the distal margin. In the forms show- 

 ing greatly atrophied tegmina and vestigial wings, or wholly lack- 

 ing wings, such venational features have disappeared, and, in 

 associating these with their proper group, the general facies and 

 less distinctive or constant characters are the only recourse. 



This is the second of the very large groups of the Pseudomopinae. 

 Though the first of these, the Blattellites, is of even much greater 

 size and has already been divided into far more genera, these two 

 groups are similar in comprehending an unusual number of yet 

 undescribed genera, in large part of tropical distribution, which 

 include a multitude of species. 



None of the numerous species assigned to Ischnoptera and found 

 in Africa, Asia, Australia and Polynesia, probably belong to this 

 genus in its restricted sense. Until large series are carefully 

 studied, however, attempts to describe new genera for these, would 

 only lead to such difficulties as were caused in the Blattellites by 

 Shelford's hasty designation and description of a number of then 

 similarly lumped, but evident, generic units." This is likewise 

 true of certain South American groups, which are represented by 

 species which have been referred to Ischnoptera, but are distinct 

 from that genus as correctly delimited. 



The genera here considered which belong to the present group 

 we list below in their proper sequence. All have been correctly 

 referred to the subfamily Pseudomopinae. 



Genotype Habitat of genotype 



1838. Ischnoptera Burnieister morio Burmeister Northern South America 



191 7. Parcoblatla nvw nama pen sy Ivani ca (DeGeer) Eastern United States 

 igi6. Symploce Hebard capilata (Saiissure) Cuba 



1916. Xei/o6/a//« Ilebard camber/ Hebard Colombia 



^* See page 25. 



