448 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 117 



segment slightly longer than two following combmed and subequal to 

 fourth; epipleura gradually narrowed, almost attammg apices of 

 elytra. Aedeagus of male relatively narrow and elongate (pi. 3, 

 fig. 17). Measurements: length 1.9-2.4 mm.; width 0.9-1.2 mm. 



Remarks. — The two North American species of Pentaphyllus are 

 very similar in appearance and difficult to characterize individually. 

 P. pallidus may be separated from P. calif ornicus, in addition to the 

 characters presented in the key, by its relatively shorter and more 

 convex body and the less robust aedeagus of the male (pi. 3, fig. 17). 

 The species occupy widely separated ranges. 



LeConte (1866) in his description of P. pallidus states that it "differs 

 from that species (P. testaceus (Hellwig)) by the body beneath being 

 not black, but of the same color as the upper surface." This is an 

 inconstant character. Specimens of both species have been studied 

 in which the ventral surface is totally or in. part black. Most spec- 

 imens studied had both surfaces of the same color. Only eight spec- 

 imens of P. testaceus have been seen. They have the short, robust 

 body of P. pallidus but have the lateral margins of the pronotum 

 even more broadly expanded and reflected than in P. californicus. The 

 dorsal vestiture of fine pale setae in P. testaceus is at least twice as 

 long as in either of the North American species and is quite conspic- 

 uous, even at low magnification. Since specimens were not available 

 for dissection, it is not known whether or not the male genitalia might 

 prove diagnostic. 



Horn (1870) was the first to call attention to the frontal tubercles 

 of the male. Otherwise, he merely repeats the remarks of LeConte 

 and states that it is "Abundant in Canada West." Blatchley (1910) 

 collected this species by sifting the debris of beech and maple stumps. 

 It is probably much more abundant than available cabinet material 

 would indicate. Hamilton (1895) took as many as 30 specimens 

 from under bark of elm in southwestern Pennsylvania. 



Type. — MCZ 4701, female. Bears a pink "Southern States" label, 

 but according to the original description, it is from Pennsylvania. 

 The ventral surface of the specimen is embedded in glue, but the 

 diagnostic characters are all clearly visible. Also in the LeConte 

 collection are 1 male and 2 females labelled "Can[ada]." 



Specimens examined. — From the follo^\dng localities, 57: 



United States: Connecticut (Cornwall). Illinois. Indiana (Dubois Co., 

 Marion Co., Monroe Co., Spencer Co.). Kentucky (Edmonton). Maryland 

 (Riverdale). Michigan (Detroit, Grand Ledge). New Jersey (Berkeley Heights). 

 Ohio (Cincinnati). Pennsylvania (Jeannette, Pittsburgh). 



Canada: Ontario, (Grimsby, Leamington), 



