ROLAND HAYWARD. '_''2> 



The species of this group divide themselves naturally into two 

 series based upon the number of dilated tarsal joints in the males. 

 In the first the two basal joints of the anterior tarsi are slightly 

 dilated; in the second the first joint only. This is shown on Plate 

 VI, figs. 15 and 16 Figure 1<>, however, represents the tarsus of 

 T. corruscus, in which the inner angle of the dilated basal joint is 

 more prolonged than in the other species. 



It is greatly to be regretted that I have been obliged to derive the 

 character for the primary division of the group from the secondary 

 sexual characters of the male, more especially as specimens of that 

 sex are much rarer than the females in the majority of our species. 



The essential character separating the present from the preceding 

 group is derived from the position of the dorsal punctures of the 

 elytra. In the species herein contained the first of these is situated 

 on the fourth interval, the second within the recurved portion of the 

 sutural stria not far from its tip. In the eighth group their position 

 is very different, the first being placed on the third stria, while the 

 second is situated either at or slightly behind the tip of the recurved 

 portion of the sutural stria, but never enclosed within it. This is 

 shown on Plate VI, figs. 7 and 8. In specimens in which the third 

 and fourth striae are obsolete the position of the second puncture will 

 indicate to which group the species should be referred. 



I regard this as the most difficult group of the genus for study. 

 Several species resemble each other very closely, while some are very 

 variable, especially in color, the extreme forms bearing a greater 

 resemblance to species separated by good structural characters than 

 to other varieties which can be connected with them by a perfect 

 series of intergrades 



The following table is the best that I have been able to devise for 

 the separation of our species. One of these, T. sequax, is not included 

 therein, the male being unknown to me, but a description of the 

 species is given below. Reference should be made in all cases to 

 the descriptions, which follow in what seems to be the best order for 

 cabi net arrangement. 



Males with the first two joints of the anterior tarsi dilated 2. 



Males with only the basal joint of the anterior tarsi dilated 5. 



2. Elytra nearly oval, sides strongly arcuate ; form slightly convex 3. 



Elytra oblong-oval ; form more or less depressed 4. 



3. Large species; piceous or nearly black, the elytra finely alutaceous with more 



or less silken lustre; sides of thorax oblique behind, hind angles very 

 obtuse, nearly obsolete. Length .12 . 13 inch albipes Lee. 



TKANS. AM. ENT. SOC. XXVI. (29) MAKCH, 1900. 



