H. C. FALL 313 



20. Front with ocular lines. 



Prothorax a little larf^(>r and more rounded on the .sides; eyes very 



slightly more distant; sutural edge blackish 37. abdominalis 



Prothorax smaller, sides less rounded; eyes slightly less distant : elytral 



suture not or scarcely darker SH. di versus 



Front without ocular lines 7G. caelatus* 



21. Front wit-h fine ocular lines; front claws of cf not apprecial)ly larger. 



•'!•'. pusillus 

 Front witliout ocular lines; front claws of o" very large . 4U. macronychus 



Group C 

 (Starred species (*) are tabulated in more than one group.) 



In this, the central and largest group of the genus, there is 

 great variation in the extent of maculation, and consequently 

 in the relative proportions of the dark and pale areas. In vittati- 

 coUis, fractus, varicolor* fortis, alacris, caelatus * nubilus * and 

 conspirator* the elytra are — at least in some individuals — almost 

 entirely yellow; while in ivenzeU* signatifrons* mdanostictus, 

 vestigialis* colifornicus* pinguescens* varicolor * and luciuosus, 

 the elytra may become almost entirely black. Tabulation has 

 proved especially difficult in some parts of this series, and the 

 student may fairly expect to find it hard at times to decide which 

 line to follow. In such cases, both alternatives may have to be 

 tested, and final judgment based upon the detailed descriptions. 



A'otatus Bowd. is for the present placed near pinguescens in 

 the table. I have not seen the unique type, and a letter of in- 

 quiry concerning it to Prof. S. J. Hunter, in charge of the Snow 

 Collection, l)rings the information that both front tarsi arc miss- 

 ing, hence the impossibility of placing it with certainty in the 

 scheme here adopted. 



1. Eyes in the cf separated by a flistance less than th(> length of the basal 



antennal joint {alacris tentativel}' placed, cf not 3^et known) 2 



Eyes in the cf separated bj' a distance equal to or greater than the length 

 of the basal antennal joint, but not greater (usually distinct Ij' less) than 



the length of the first two joiiats 6 



Eyes in the cf separated by a distance greater than the length of the basal 

 two joints of the antennae (not at all greater in one example of roboris, 

 scarcely so in californicus and onlj- slightly greater in precaritts) 18 



2. Front claws of d' very small, not at all larger than those of the middle and 



hind feet. (Arizona.) 43. buUatus 



Front claws of d' more or less enlarged 3 



TR.\NS. AM. ENT. SOC, XLI. 



