l^^l'S] Alydince of the United States 2(39 



i;i. Alydus eurinus vSa\'. 



Lygueus eurinus Say (1825) 324', (lcS59) 247. 



Alydus eurinus Uhler (1872) 401^, (1875) 832^ (1876) 293', (1877a) 40(P (!87ha) -)04'' 

 (1878b) 384"; Distant (1881) 157; Provancher (1885) 53**; Van IXv/cv (1880)9' 

 (1894)"', (1903)", (1908)'=. (1917)'^; Osborn (1892)'^ (1900)'-\ Montandon 

 (1893)"'; Gillette and Baker (1895)'"; Montgomery (1902)'s- Wirtncr (]'K)4)i3- 

 Snow (1904)=", (1906b)="; Bueno (1905)-'', (1908)==, ( 1910a )-'3, (19101))-'' (Vn-^Y^^'- 

 Bueno and Brimley (1907)-'"; Tucker (1907a) (19071))='; Bueno and En^^eihardt 

 (1910)=«; Smith (1910)-'»; Barber (1911); Parshlev (1914)3o 



Alydus (Iter Dallas (1852) 478; Stal (1870) 213=". 



Alydiis pluto Prov. (1885) .56; (?) Osborn (1892), (1894), (1900). 



Coriscus vicarius Prov. (1887) 175, in error. 



Description. — Head, thorax, venter, and femora piceou.s Ijlaek, 

 verging at times to dark eastaneou.s and sometimes apparently- griseus 

 in pilose individuals. Fla\'esccnt spots at base of head (as in plido) and 

 along margins of alxlomen. Antenna; castaneous marked at the tip 

 of eaeh segment with piceous; apical segment fuscous; first shorter 

 than second or third, which together are subequal to or a little longer 

 than fourth. 



Caudal aspect of clasper of male (Fig. .3) with a tumid hemispherical 

 area at base from which arises a propeller-shaped lobe, showing a broad 

 eaudo-mesal face; claspers approximate except along caudal margin 

 Female with lateral plates of hypopygium (Fig. 4) flat, acute at tip, 

 convergent; mesal plates obliquely truncate, sixth ventral segment 

 with carina \^er>- short, indistinct, or wanting. 



The only Alydus reported from every section of the United 

 States is A. eurinus, although in Wisconsin it is not as wide- 

 spread as the following species and is rare north of Madison. 

 Throughout its range the adults are numerous in late summer 

 along road sides and the edges of woods on goldenrod and other 

 fall fiow^ers. The young have been bred on Astragulus in 

 Colorado, appearing the middle of May. 



The recorded distribution is as follows: Quebec '^-^-, 

 Ontario^ Maine^-^«, New Hampshire'--\ Massachusetts'-'«-l^ 

 Connecticut^\ New York io-2i-2->-24-25^ ^^^ Jersey-'---', Penn- 

 sylvanial^ Virginia-\ North Carolina-«-2>^, Georgia''*, Florida'^ 

 Ohio^-''^-^, Illinois^'-'', Wisconsin''-'-'"-\ Iowa''-''-'', ' Missouri"' 

 Arkansas', Nebraska^ Kansas"-^, Texas\ Dakota",' Montana', 

 Colorado^-i^ Arizona'--'\ Vtah'^ California'''. 



The characters appearing in the literature do not serve to 

 differentiate this species from .4. pluto on one hand and A. 

 conspersus on the other. In fact it is necessary to examine 

 the genitaHa in order to distinguish them. Some of the eurinus 

 of the upper Mississippi valley are densely black and very robust, 

 closely resembling A. pluto. These may be known as: 



