A Bevision of the Genus Synthocus. \ ] ,'.,0J, 



species are found, and two species occur still farther no™ c^n' the 

 borders of the Western Sudan ; but in East Africa the genus 

 appears to be quite unrepresented. 



As the head and rostrum are very uniform in structure through- 

 out the genus and appear to offer no characters which would be 

 of use in discriminating the species, no detailed description of 

 them has been given. 



Specierum Conspectus, 



1. (18) Coxse mediae separatee ; processus intercoxales inter eas conjuncti. 



2. ( 3 ) Prothorax lobo antico dorsali in medio profunde emarginato et carinis 



duabus alte elevatis instructo ; elytra a basi usque ad declivitatem valde 

 dilatata, subtriangularia, lateribus rectis, humeris nullis. 



1. S. hopei, Boh. 



3. ( 2 ) Prothorax lobo antico dorsali simpliciter rotundato nee carinato ; elytra 



postice non dilatata, humeris evidentibus. 



4. ( 7 ) Elytra interstitiis tribus aut quinque in singulo regulariter crenato- 



costatis, interstitio secundo evidenter elevato et postice subcristato, 

 area suturali a basi ad apicem late deplanato et levi. 



5. ( 6 ) Elytra humeris subangulatis, interstitiis 3 et 5 prope basin tantum costatis, 



postice deplanatis 13. S. nigropictus, Pasc. 



6. ( 5 ) Elytra humeris rotundatis, interstitiis 3 et 5 usque ad declivitatem 



costatis 14. S. adustns,V&QC. 



7. ( 4 ) Elytra aut bifariam tantum in singulo costata aut remote tuberculata, 



interstitio secundo non elevato, area suturali non definite deplanato. 



8. ( 9 ) Elytra convexa, postice rotundato-declivia, tuberculis flavis remotis 



obtusis triplici serie in singulo instructa. 



12. S.fiavotuherosus, sp. nov. 



9. ( 8 ) Elytra in dorso plana aut depressa, postice abrupte angulato-declivia, in 



singulo bifariam tantum tuberculata aut costata. 



10. (13) Elytra comparate breviora et latiora, humeris non angulato-productis, 



lateribus rotundatis aut subparallelis ; tarsi breves, crassi, articulo 

 quarto sesqui-longiore quam latiore. 



11. (12) Prothorax longior quam latior ; elytra latiora quam longiora, lateribus 



rotundatis, serie tuberculorum externa aeque ac serie interna elevata ; 

 pedes setis nigris adspersi, tibiis levibus . . . . 11. S. reichei, Boh. 



12. (11). Prothorax non longior quam latior ; elytra quadrata, lateribus sub- 



parallelis, serie tuberculorum externa sub serie interna evidenter 

 demissa ; pedes setis albis raris adspersi, tibiis scabris. 



10. S. parvus. Per. 



13. (10) Elytra longiora, humeris fortiter angulato-productis, lateribus postice 



gradatim angustatis ; tarsi longiores, minus crassi, articulo quarto plus 

 duplo longiore quam latiore. 



14. (15) Prothorax medio utrinque obtuse angulata, postice angustata ; elytra 



angulis baseos externis prothoracem non excedentibus, costa dorsali 

 postice subrecta 2. *S. truncatus, Boh. 



15. (14) Prothorax utrinque rotundata nee angulata, postice vix angustata. 



16. (17) Elytra angulis baseos externis prothoracem excedentibus et antice paulum 



productis, costa dorsali postice subrecta . . . . i. S. dorsalis, Fahr. 



17. (16) Elytra angulis baseos externis prothoracem non excedentibus, costa dorsali 



versus declivitatem exterius in angulum obtusum deflexa et costam 

 lateralem ibi superne occultante S. S. sinuatus, sp. nov. 



