NORTH AMERICAN GEOTRUPINAE — HOWDEN 245 



brown. Structure and angle of clypeus, eye canthus, tubercles, and 

 vertex very similar to blackburnii. No constant differences were noted. 

 In general there appear to be a few more punctures near the clypeal 

 base in excrementi than in blackburnii. Pronotum completely moj- 

 gined, but usually not as convex as in specimens of blackburnii. 

 Coarse punctures either confined to sides or scattered unevenly over 

 entire pronotum, most numerous laterally and along midline. A cluster 

 of punctures usually forms a median circular depression on each side 

 of the pronotum. Minute secondary punctures almost always evident 

 laterpUy and in many cases scattered over the entire pronotum. 

 The posterior half of the pronotal midline may or may not be indented. 

 Scutellum and elytra like those of blackburnii, except that in excrementi 

 the elytra are usually less convex and have slightly more pronounced 

 strial punctures. 



Foretibia of male differing from the female by having an expanded 

 apical tooth and a row of conical teeth on the undersurface, both of 

 which are lacldng in the female. The conical teeth on the undersurface 

 of the tibia of the males are highest medially, becoming smaller both 

 basally and distally (pi. 2, fig. 11). In other respects the legs are 

 similar in structure to blackburnii. 



Genitalia and genital capsule of male are well developed, the para- 

 meres of the male genitalia being quite distinctive (pi. 4, fig. 6). The 

 most readUy discernible characteristic is the basal portion of the right 

 paramere, which is moderately elongate, but shorter and thicker than 

 in blackburnii. In none of the examples studied did it extend beyond 

 the basal tip of the widened left paramere. The left paramere is more 

 elongate than it is in specimens of blackburnii, and in many examples, 

 particularly from the southwestern portion of the range, the inner 

 portion of the paramere has many small spines. 



Neotype: Male, Columbia, Mo., Apr. 2, 1935, Start (USNM). 



As Say listed two places in Missouri and the State of Pennsylvania 

 as localities, I have picked Missouri as the type locality. 



Variation is the same as that given for blackburnii. The subspecies 

 excrementi is rather difficult to separate from blackburnii by external 

 characteristics. Females are almost impossible to differentiate, but 

 in general the presence of numerous, fairly distinct secondary punc- 

 tures on the lateral portions of the prothorax will separate female 

 excrementi from blackburnii. The males may be easily separated on 

 genital characteristics (pi. 4, fig. 6) and by the conical teeth on the 

 inner flattened surface of the foretibia which are longest in the middle 

 in excrementi, while in the males of blackburnii the distal tooth is 

 longest (p. 2, fig. 11). 



To my knowledge, this subspecies has never been differentiated 

 before. It is very probable that Say's description of excrementi, 



