191 S.] V. II. Ckavei.y: Passalidae of the World. 69 



sutiiif. IK) tulxTch's hciiij; (l('Vfl(i])i'(l ill this jxisitioii in specimens from Africa. Kiuvert 

 has, it is true, described from ^hidagascar one species of each of his otherwi.se purely African 

 genera Eriouomus and Didiwoides ; but it remains to be seen whether he was right. In 

 the case of the fomier genus the sentence "" Der ganze Clypeus in der Breite der ganzen 

 Obcrlijipe scharf vorgezogen "' suggests, for instance, that stiidi may belong in reality 

 to the new genus Mtdmjnsuhis, established below to receive the only species of 

 Solenocyclinae known to me in which the clypeus is exposed, and the pair of marginal 

 tubercles most characteristic of the family as a whole — i.e., those immediately above the 

 lateral extremities of the clypeus — are entirely absent. 



None of the Malagasy genera hitherto described contain very many species ; and the 

 differences between them may advantageously I think be regarded as specific rather than 

 generic. I propose, therefore, to unite all of them under the name Solenocyclus. 



Some of the African genera appear to be decidedly larger ; but in spite of this I am 

 unable to find satisfactory characters by which to define more than two. I propo.se, 

 therefore, to unite under the name Pentalobus, Kaup, all species with hairy sides to the 

 metasternum and a more or less distinct tubercle or pair of tubercles or excavation in 

 the middle of the anterior margin of the head ; and to unite under the name Erionomust 

 Kaup, all species in which the sides of the metasternum are hairless and the middle of the 

 .anterior margin of the head is straight. 



The genera of Solenocyclinae may now be defined as follows : — 



' A more or loss di.stinct pair of iiiar^jiiial tubercles present imnie- 



\ diatelv on the inner side of the fronto-vertical sutures (Mala- 



I jiasy forms) . . . . . . . . . . . 2. 



( Tubercles not present in this position (African forms) . . . . . . ;}. 



\ The clypeus exposed . . . . . . . . Malagasahis, p. 69. 



" ( The clypeus hidden . . . . . . Solenocyclus, p. 70. 



/ The sides of the metasternum hairless ; the anterior margin of 



\ the head more or less distinctly notched in the middle line, 

 3-\ or with a median tubercle .. .. Pentalobus, p. 72. 



/ The sides of the metasternum hairy : the anterior margin of 



V the iiead witliout any median notch or tubercle .. Erionomus, p. 71. 



(Jcnus MALAGASALUS, n. gen. 

 Type, Malagasah(s cl>/pcat)is, n. sp. 



The clypeus exposed ; a pair of marginal tubercles present immediately on the inner 

 .side of tlie fninto-vertical sutures; the sides of the metasternum hairless. 



Malagasalus clypeatus, u. sp. 

 Fij;. Vlll, I, p. 70. 

 Two specimens from Feiitrive. .Madagascar. Length 34 nmi. 



The antennae each have three well developed lamellae. The labrum is concave in 

 front, convex at the sides, slightly luirrower behind than in front. The central tubercle 

 is strongly elevated above the short parietal ridges, but is somewhat obtuse. The frontal 

 ridges diverge from it in an angle of about !»(»'' : they extend to the stronglv developed 



