464 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ni 



body shows great difference between the smallest and largest speci- 

 mens seen, 5.25 to 7.78 mm; the smaller specimens were all from the 

 southern part of the range, with the smallest being from Bermuda. 

 But not all southern specimens are small; many of them are as large 

 as any of the northern ones, and intermediate sizes exist; consequently, 

 the name uhleri is not necessary for the smaller specimens. 



Depending on the maturity of the individual at the time of its death, 

 the color varied from yellowish brown through reddish brown and 

 piceus ("var. a. picea" of bilineatus Say, 1825) to black with the legs, 

 particularly the femora, often being reddish brown {femoralis Herrick- 

 Schaeffer). These above-mentioned variations have been confusing, 

 but since nearly any one of them may be found in any part of the 

 range, there can be no other conclusion but that only one quite variable 

 species is involved. 



The application of Say's name bilineatus employed here is that com- 

 monly followed by all other workers. Pangeus bilineatus is considered 

 the common species of the eastern United States. Since most of 

 Say's collection has been destroyed, it is quite probable that the type 

 of bilineatus was destroyed with it. This leaves the species without a 

 type, but since the presently used assignment is so universally adopted 

 there can be little objection to continuing the practice. Although 

 Signoret apparently intended to follow this plan, his figure 113 on 

 plate 9 of his 1882 "Revision" shov/s one important difference from 

 all specimens of the species seen during this study. No specimen 

 showed the quadrate terminal appendage to the osteolar peritreme. 

 Without doubt, this misrepresentation aided Signoret in separating 

 several "new species" from bilineatus. Considermg in order the older 

 names and those doubtful Signoret species of which Signoret material 

 was available for study, the reasons for synonymizing the names 

 are given below. 



Herrick-Schaeffer's two species, Cydnus rugifrons from "Georgien 

 in Amerika"and Cydnus femoralis from "Lankaster aus Nordamerika," 

 were described from individual variants as indicated in the present 

 discussion of the variation that occurs in this species (supra). 



Walker's Aethus fortis from Mexico. Notes on the type furnished 

 by Dr. China confirm the general acceptance of this name as a syn- 

 onjrm of bilineatus. 



Pangoeus vicinus Signoret, "Guayaquil." A female specunen in 

 the Signoret collection (Wien) is labeled "vicinus dot Signoret," but 

 does not bear a type label. In addition, the specimen is labeled as 

 being from "Mexico," not from the type locality given in the original 

 description. In view of the description of the limited mesopleural 

 evaporatorium of vicinus and the present study revealing no members 

 of the subgenus Homaloporus from the South American continent, 



