THE CANADIAN ENTOMOLOGIST 91 



C. punctatus Sign. The greatly pnxluced and acutely pointed last abdom- 

 inal segment of the female serves as a character to set this off from other 

 species. HoweNcr, in tliis respect the females of bohemanii Sign, approach 

 punctatus, and I am unable to separate the males of these two species. C. 

 punctatus is limited to the southwest, while bohemanii occurs over the entire 

 eastern half of the United States. While for the time being it is wise to keep 

 these two forms distinct and as separate species, yet the author surmises that 

 one may be a locality form of the other, and at some future time with increased 

 evidence it may be best to consider one a variety of the other. 



C. bohemanii Sign, is probably the most common species found in the East 

 and Central States. Typical specimens are extremely dark in colour. The last 

 abdominal segment of the female is produced more than any other species excejit 

 punctatus Sign. 



C. scutatus Stal. is the largest species in North America, and occurs from 

 British Columbia south into Mexico. Its generally large size and bluntly 

 pointed scutellum will serve to distinguish the species. In colour it vafies con- 

 siderably. Typical specimens are dark with connexivum heavily marked. 



C. indentatus Hambl. is a comparatively small form that can only be separ- 

 ated from scutatus Stal. by its size and the fact that its sternum is black while 

 that of scutatus is normally light-coloured. Both are western species. 



C. sides Fabr. is very variable in size and general colour, but is readily 

 separable from the other species by dorsal transverse, black bands or markings 

 on the third, fourth and fifth abdominal segments. This characteristic colour 

 marking is always present, although in some specimens examined it has become 

 less prominent or faded. Numerous specimens exhibit much reddish coloration. 

 Some authors would undoubtedly establish numerous varieties based upon 

 variations of colour and size, but the writer is prone to believe that such dif- 

 ferences come from climatic and food conditions. A close study of the external 

 anatomy of these so-called forms reveals no structural differences. I do not 

 agree to the advisability of considering pictipes Stal. a distinct variety. It is 

 also a cosmopolitan species. 



C. lateralis Say occurs over the entire United States and southward. There 

 are no outstanding features that will readily serve to separate this from other 

 species. The process of elimination in the determination of species will apply 

 to advantage. If specimens in question cannot be placed in other species they 

 are usually called lateralis. The acutely pointed scutellum and lack of markings 

 on the connexivum are generally used as diagnostic characters. It is very 

 variable in size and colour, some specimens being quite dark or reddish and 

 others entirely pale yellow. I am unable to separate Uhler's validus from 

 lateralis, except in size and the slight colour markings on the connexivum. 

 However, I* have seen innumerable gradations in size from an extra large, so- 

 called validus to a minute lateralis, and have been unable to separate them by 

 structural differences. Also even some nearly typical lateralis will exhibit 

 slight indications of colour markings on the connexivum. For the time being I 

 consider it advisable to consider validus as a variety of lateralis until more 

 biological evidence is at hand. 



C. crassicornis Linn, and viridicatus Uhl. These two species form a group 

 quite distinct from all other species, and can be most easily recognized by the 



