HYALYMENUS.—ALYDUS, 157 
Alydus affinis, Hope, Cat. Hem. ii. p.19; Dall. List Hem. ii. p. 477. 22”. 
Alydus sinuatus, H.-S. Wanz. Ins. viii. p. 98, f. 865 * (nec Fabr.). 
Alydus recurvus, H.-S, Wanz. Ins. viii. p. 98, f. 866°. | 
Alydus pallens, Dall. List Hem. ii. p. 476. 20°. 
Camptopus pectoralis, Stal, Rio Hem. i. p. 34. 1”. 
Hyalymenus tarsatus, Stal, En. Hem. i. p. 212. 11°; Ubler, Bull. U.S. Geol. & Geog. Surv. ii. 
p. 294°. 
Stoll, Pun. f. 214. 
Var. a. pallescens, Stal, En. Hem. i. p. 212. 
Alydus atratus, Fabr. Syst. Rhynch. p. 251. 12. 
Alydus obscurus, Hope, Cat. Hem. ii. p. 19. 
Var. b. infuscatus, Stal, En. Hem. 1. p. 212. 
Hyalymenus (Tivarbus) tarsatus, Stal, Hem. Fabr. 1. p. 62. 3. 
Hab. Norta America, California 9»—Mexico?48® (coll. Sallé), Valladolid, Yucatan 
(Gaumer); GuateMALA, San Gerdnimo, Panima, San Juan, Cubilguitz (Champion) ; 
Honpuras®; Panama (coll. Dist.).—West Inpiss°, Jamaica?; CoLomBia? ®, Bogota®; 
Guiana, Demerara! (coll. Dist.); Braziu}°°8, Para®, Rio Janeiro? 8, 
This is a most variable species—as Stal remarks, “‘species quoad magnitudinem, 
colorem, picturam dorsi abdominis ventrisque, nec non formam pedum posticorum 
maxime varians.” In the most melanic forms the antenne are ochraceous, the apical 
joint being sometimes somewhat darker but always annulated with luteous near the base. 
In all the pale-coloured varieties the sternum is ornamented on each side near the cox 
with large luteous levigate spots—a character which, with the colour of the antenne, 
has been used by Stél® as a sectional character for the genus; but in the melanic 
specimens these sternal spots are obsolete; and therefore little differential aid is thus 
afforded. 
ALYDUS. 
Alydus, Faby. Syst. Rhynch. p. 248 (1803); Stal, Ofv. Vet.-Ak. Férh. 1867, p. 542; Hem. Afr. 
ii. p. 7 (1865); En. Hem. i. p. 213 (1870); ib. iii. p. 89 (1873). 
Burtinus, Stal, Ofv. Vet.-Ak. Férh. 1859, p. 459. 
Megalotomus, Fieb. Eur. Hem. pp. 58, 226 (1861). 
The apices of the posterior tibie are unarmed, a character which, as previously 
remarked, distinguishes Alydus from Hyalymenus. Stal has divided Alydus into four 
subgenera, most of which have been adopted by Prof. Uhler as genera. Neither of these 
methods has been here followed. The genus as at present defined is well represented 
both in the Nearctic and Neotropical regions. 
1. Alydus eurinus. 
Lygeus eurinus, Say, Journ. Acad. Nat. Sci. Philad. iv. p. 824. 5 *; Compl. Writ. ii. p. 247. 5. 
Alydus eurinus, Stal, En. Hem. i. p. 218. 3° (exclud. A. pilosulus, H.-S.); Uhler, Hayden’s Surv. 
