156 ENTOMOLOGICAL SOCIETY 



Originally the species was described by Say as Pamera con- 

 stricta from the United States.* Stal placed Say's species in 

 his genus Ligyrocoris.-\ The species of this genus are mainly 

 characterized by having on both sides of the abdomen, at the 

 base, a lunate vitta which is very finely striated and not pubes 

 cent. 



Among my specimens I found some with a vitta and others 

 without a trace of it. This made it impossible to decide which 

 form really was the species Say had described, since his descrip 

 tion fits both forms equally well and since he makes no mention 

 of any vittae on the abdomen. Unfortunately Say's types have 

 been lost, but many species in the Harris Collection at the Bos 

 ton Society of Natural History are named by Say, according to 

 Mr. Ph. R. Uhler, who years ago worked up and arranged this 

 collection.]: Mr. Uhler cites Say's species Pamera constricta 

 as belonging to the genus Ligyrocoris Stal, referring to No. 

 122, Harris Collection, Milton, Aug. 15, 1831, " determined as 

 Pamera constricta by Mr. Say" (1. c., p. ^89). Mr. S. Hen- 

 shaw, of the Museum of Comparative Zoology, Cambridge, 

 Massachusetts, has been kind enough to compare the two differ 

 ent forms with the specimen in the Harris Collection. His an 

 swer reads as follows : "Harris' specimen is badly eaten, but 

 there is enough on one side to show the vitta on that side." 

 This might settle now any doubt as to the determination of Say's 

 Ligyrocoris constrictus. ' , 



I was puzzled for some time as to where I should properly 

 place the specimens without a lunate vitta, until I found in the 

 Biologia Centrali-Americana a description by Mr. Distant of a 

 new genus, Perigenes, based on the new species P. dispositus 

 from Guatemala. The description of the genus is very short 

 and concise: " Form and shape of Ligyrocoris Stal, but with 

 out the lunate vittae to the under surface of the abdomen ; poste 

 rior legs shorter ; antennas shorter, the third joint with the apex 

 distinctly incrassated." Following this description I have no 

 hesitation in placing my specimens in this genus, but I venture 

 to describe this form as a new species on account of some differ 

 ences, even if these are but slight. 



Perigenes fa/lax n. sp. 



Body golden pubescent. Head, thorax and side margins of abdomen 

 covered with soft, long hairs. Head, abdomen and humeral angles of 



* Say's Entomology of North America, LeConte, I, p. 332. 



t Enumeratio Hemipterorum, part IV, p. 146. 1874. 



J See his paper " Notices of the Hemiptera-Heteroptera in the collec 

 tion of the late T. W. Harris. M. D." (Proc. Boston Soc. Nat. Hist., 

 XIX., pp. 365-446, 1878. 



Biol. C.-Am., Hemiptera-Heteroptera, I., p. 396, PI. 34, Fig. 25, 

 March, 1893. 



