134 , . 



with copious collections from tlie various regions have enabled me to 

 recognize under older names several of the groups I take to be of speci- 

 fic value. But most of the older names should under no conditions be 

 used without careful comparison with the types — ^determinations from 

 the descriptions alone would usually be worthless. There is no doubt 

 but that many of the names represent merely color forms, and like- 

 wise some of the names now in use will doubtless be found exactly 

 equivalent to older names if the types were available for study. Tn 

 other collections which I have seen, the uttermost confusion has resulted 

 from the attempt at grouping according to the color descriptions. In 

 the same species there may be a very wide variation in this respect in 

 a lot taken together on the same food plant, but such a lot will usually 

 be found remarkably uniform in the finer structural details. 



The status of the genus in America as to an evolutionary point of 

 view is apparently wholly opposed to that presented in Europe. In 

 America the species of typical Nysius, all belong to one general type 

 and present no wide subgeneric divergences, and possess a most remar- 

 kably high degree of individual variation in size and coloration. Some 

 of the subgeneric groups of the old genus A^yshi-i, I regard as better 

 defined genera than many groups of the Lygaeidae commonly recogni- 

 zed as such. In America we have two very distinct groups of generic 

 value, Nysius and Ortholomns. 



Synopsis of Genera. 

 A. — Costal margin of corium straight only near the base if at all, and 

 beyond this more or less rounded; head extended on either side be- 

 yond anterior angles of pronotum by less than half width of eyes, 

 the exposed area back of eyes small; bucculae long or short; corium 

 with few fuscous markings and the membrane usually nearly or 



quite clear Nysius Dall. 



AA. — Costal margin of corium straigt^, throughout, the two sides 

 parallel or even converging; hea^. extended on either side be- 

 yond anterior angles of pronotum oy more than half the width 

 of the eyes, the exposed area back of eyes large; bucculae 

 alwals less than half the length of gular area; corium more or 

 less distinctly densely mottled, and the membrane more or less 

 fuscous spotted, or entirely fuliginous Ortholomus Stal. 



Genus Nysiuff Dall. 

 Synopsis of Species. 

 A. — Costal margin of corium straight for a short distance at base, then 

 distinctly outcurved. 

 B. — 'Bucculae broad, and less than hall /ength of gular region; costal 

 margin of corium straight at base for only about one-fourth of 

 scutel; a very large species of the west and south californicus Stal. 

 BB. — Bucculae always more than half length of gular region, the 

 shorter forms very narrow; size medium to small. 



