168 FREDERICK BLANCH ARD. 



variation of the number and position of tlie tarsal setaj in the same 

 species, the result of the examination of thirteen females of F. trian- 

 gularis may be instanced : In eight specimens the last joint was bisetose. 

 In one specimen the last joint of the left tarsus was bisetose, and that 

 of the right trisetose. In another the last joint of the left tarsus was 

 trisetose, the extra seta shorter and finer, and that of the right bisetose. 

 Finally two specimens had the last joint bisetose and the third joint of 

 both tarsi with a single seta at lower apical angle. 



Table of Species. 



Clypeus deeply emarginate and with two long teeth in the emargination ; black, 



opaque; hairs beneath distinctly ferruginous Pluto. 



Clypeus at most feebly sinuate in front. 



Elytra smooth, shining, obsoletely striate; dark green or blue, club of antennaj 



fuscous quadridens. 



Elytra coarsely, deeply and more or less confluently punctured ; striae distinct, 

 club of antennae pale rufous. 

 Hind angles of thorax broadly rounded; side margins in front irregularly 

 serrate; declivity of thorax with the sides converging behind in well de- 

 veloped males difiorinis. 



Hind angles as usual, distinct, obtuse; side margins entire, declivity with 



sides diverging behind in well developed males cni'iiirex. 



Elytra not deeply punctate, intervals more or less convex. 



Thorax densely granulate; club of antennae fuscous; intervals of elytra feebly 

 convex and with subobsolete, coarse, shallow, more or less confluent punc- 

 tures triangularis. 



Thorax rugose or scabrous; intervals of elytra more convex. 



Club of antennae pale rufous: intervals punctate, much as in triangularis. 



igneus. 



Club of antennas fuscous ; elytra deeply striate, intervals very convex, 



nearly smooth, sparsely punctulate mexicanus. 



PHABJ.KITS. 



McLeay, Hor. Ent. ISli), I, p. 124. 



1. P. Pluto Harold, Ann. Soc. Ent. Fr. 186.''., series IV, vol. Ill, p. 104 : morio 

 Lee, Smith. Misc. Coll. VI, p. 36. 



Length 21 mm. Ariz., Mex. (Tamaulipas) 



2. P. quadridens Say (Copris), Bost. Jour. 1837, I, p. 176; ed. LeConte II, 

 p. 6.50 ; P. violaceus Laporte, Hist. Nat. II, p. 81 ; laevipennis Sturm, Cat. 184.'i, p. 

 :;.34, pi. 2, fig. 3; evippus Dej. Cat. 1836, 3 ed., p. 155. 



Length 10-20 mm. Ariz., Mex. 



3. P. difibrinis Lee, Jour. Acad. 1847, series II, v. I, p. 86. 



Varies in color, with thorax green and elytra blue, or thorax cupreous 

 and elytra green. Intervals of elytra not costate. 

 Tjength 19-20 mm. Texas, N. Mex. 



