1918.] F. H. Gravely : Passalidae of the World. 75 



Erionomus trichostigmoides n. sp. 

 Fig. VIII, 4, p. 70. 



Two specimens, one from Dar-es-Salaam, and one said to come from Santa Catharina 

 in S. E. Brazil. Length 27-5-29-5 mm. 



This species bears a close superficial resemblance to species of the Oriental genus 

 TricJiostigmus from which, however, it may readily be distinguished by the structure of 

 the mandibles, and of the lateral areas of the metasternum, which resemble those of its 

 African allies. 



The antennal lamellae are extremely short. The surface of the head is polished and 

 somewhat rugulose ; the frontal area is fully as broad as long, and the inner tubercles are 

 somewhat indistinct. The pronotum is without strong punctures ; its grooves resemble 

 those found in other members of the genus. The mesosternum is punctured and hairy 

 in front, and roughened and hairy behind, with a small smooth and hairless area in the 

 middle. The metasternum is punctured and hairy, except in the central and posterior 

 parts of the central area. The punctures in the grooves of the elytra are more or less 

 obsolete, but the eighth to tenth ribs are covered with small hair-bearing punctures. 



Erionomus alterego (Kuwert). 

 Eriostermts alterego, Kuwert, 1898, p. 138. 



Two specimens from Abetefi, Ashanti. Length 29-31 mm. 



The antennal lamellae are very short. The anterior margin of the head bears a more or 

 less distinct median pair of marginal tubercles, the outer tubercles are somewhat small, 

 and the secondary tubercles on the outer side of them are broadly truncate. The pronotum 

 resembles that of E. trichostigmoides, except that the marginal grooves are more strongly 

 punctured. The smooth and hairless central areas of the mesosternum and metasternum 

 are much larger, though the punctures on the latter plate are stronger where they occur. 

 The elytra are hairless except at the shoulders ; their dorsal grooves are scarcely, their lateral 

 grooves distinctly but not transversely, punctured. 



Erionomus planiceps (Eschscholtz). 

 Fig. VIII, 5, p. 70. 

 Passalus planiceps, Eschscholtz, 1829, pp. 22-23. 



Three specimens from Guinea and two from Abetefi, Ashanti. Length 38-0-4 1-5 mm. 



In this species the outer tubercles are directed upwards instead of forwards, and appear 

 in consequence to be situated a little behind the anterior margin of the head, beneath- 

 which, however, dissection shows the true clypeus to be hidden as usual. The marginal 

 grooves of the pronotum are not strongly punctured. The posterior intermediate areas of 

 the metasternum bear a posterior marginal band of fine close punctures, the rest of these 

 areas being smooth much as in E. alterego, which the present species also resembles in all 

 other respects. 



The above-mentioned species of Erionomus may be distinguished as follows : — 



( Each antenna with four long slender lamellae . . . . E. palini, p. 74. 



( Each antenna with three short stout lamellae . . . . . . . . 2... 



l2 



