STENOCERUS. 321 
d. Central area of pronotum and a round sutural patch on elytra velvety-black, 
sharply defined . . 2. 2. ew... es [sigillatus, sp. n.; Brazil.] 
No such black marking . a 
e. Rostrum with a fine mesial raised line within the impression . . . . . . Species No. 3. 
Rostrum without that line; ¢ with small mesial tubercles on abdomen. . 
[varipes, Fahr. (1889); Brazil.] 
Rostrum without that line; ¢ without abdominal tubercles. 
[angulicollis, Jekel (1855) ; Colombia. | 
Jekel’s Stenocerus amazone, brunnescens, longulus, meaxicanus, migratorius, and tessellatus are all the same 
species; his testudo is the same as Erichson’s velatus, and his verticalis the same as Fihreus’s varipes. 
Erichson’s aspis and Reed’s vidali are doubtless species of Dinocentrus. Motschoulsky’s variegatus is the 
Central-American form of longulus, the name variegatus sinking as a synonym of mexicanus. Montrouzier’s 
macrophthalmus is a Litocerus, and his quadrituberculatus a Hylopemon (quadrituberculatus standing in the 
Munich Catalogue, p. 2730, under Stenocerus and Hylopemon). 
1. Stenocerus velatus. 
Stenocerus velatus, Erichson, Wiegm. Arch. Naturg. xii. 1, p. 125. n. 1 (1847). 
There are apparently two geographical forms of this insect, one from South America 
(velatus=testudo, Jekel, Ins. Saund. i. p. 104), the other from Panama :— 
Subsp. nigritarsis. 
Stenocerus testudo, ab. nigritarsis, Jordan, Stett. ent. Zeit. lvi. p. 166 (1895) *. 
©. Pronotum and tarsi black. 
Hab. Panama, Chiriqui (Mus. Tring, ex Staudinger & Bang- Haas). 
Only one example (2) of this form is known, which I originally described as an 
individual aberration, but which I now take to be a representative of a melanic race 
peculiar to (the southern states of) Central America, considering that the Central- 
American specimens of the next species show also some melanism in the tarsi. 
2. Stenocerus longulus. 
Stenocerus longulus, Jekel, Ins. Saund. i. p. 106 (1855) *. 
Hab. Soutu America !. 
Very variable in size, shape, and colour. In the ¢ the anal ventral segment is convex ; in the 2 it is some- 
what impressed, bearing a tuft in front of the impression. What I consider to be individual varieties of 
S. longulus have been described by Jekel as representing five distinct species. The differential characters 
given by Jekel do not hold good, nor have I been able to find new distinctions. In some specimens the 
lateral carina of the prothorax is more strongly angulate than in others (side view), and in some males 
with this character the second abdominal segment bears a small mesial apical rounded tubercle or swelling. 
The mesosternal process may be strongly or rather feebly bituberculate. The elytra may be comparatively 
short, resembling those of S. fulvipes, or more slender. All such distinctions are inconstant and occur 
in a greater or less degree of development according to individuals. However, the Central-American 
specimens are, on the whole, slightly different from those from South America. The mesial carina of the 
rostrum is generally nearly effaced at the base of the rostrum and does not extend beyond the eyes on 
