396 Annals of the Carnegie Museum. 



These insects have been separated by the use of such characters as 

 comparative length and width of tegmina, length of wing, form of 

 body, form of pronotum, etc., also by the presence or absence of dusky 

 markings on the basal and sub-basal antennal joints. This latter 

 character has been adopted in recent years as quite characteristic, 

 at least for our North American forms. 



In food-habits these crickets are supposed to be partially insectivor- 

 ous, feeding upon aphids and other small delicate insects, which they 

 find among the foliage which affords them shelter. Their eggs are 

 deposited in the buds, bark, and stems of various plants. 



Eight species of this genus have been credited to South American 

 countries. The specimens at hand in part can be referred to one or 

 another of those species. Two of these specimens do not, however, 

 appear to belong with any of them. The subjoined synoptical key 

 will aid in their recognition: 



Synopsis of the South American Species of CEcanthus. 

 A. First and second antennal joints obtusely tuberculate below, each marked 



with a black dot. [Cuba, Central America] niveus DeGeer. 



A A. First and second antennal joints not tuberculate, but first joint sometimes 

 swollen internally. 

 b. Basal antennal joints unicolorous, without black markings. First joint 



swollen internally. [Trinidad] immacidata Bruner. 



bb. First and second antennal joints marked below with black. 

 c. Tegmina and wings about equal in length. 



d. Size minute (male to tip of tegmina 9.5-10 mm.), graceful. First 

 antennal joint gently swollen internally, faintly lined with brown. 



tninutus Saussure. 

 lid. Size larger (male to tip of tegmina 13 mm.), robust. First antennal 

 joint a little swollen below, the first and second longitudinally lined 

 with black. [Chapada and Rio Grande do Sul, Brazil] 



lineolalus Saussure. 

 cc. Tegmina shorter than the somewhat caudate wings. 



d. First antennal joint marked below with a longitudinal line and an 

 apical dot, the second with a dot. [Mexico, Argentina]. 



argenlinus Saussure. 

 dd. First and second antennal joints below both marked with longi- 

 tudinal black lines. 

 e. Larger (female to tip of wings 23 mm.) very slender. [Brazil] 



varicornis Walker. 

 ee. Smaller (female 16-18 mm.), slender. [Santarcm and interior 



Brazil] tenuis Walker. ^ 



' Walker's descriptions are so poor and meager that it is next to impossible for 

 one to definitely determine the insects referred to. Evidently the species vari- 

 cornis, tenuis, and periivianus are very similar, if not identical. 



