1895. PROCEEDINGS OF TEE NATIONAL MUSEUM. 83 



Lateral surface more or less beset with coalc tubercles; above the bases of the 

 le,a,s two gradually rounded prominences, densely tuberculate: dorsum nearly 

 always tuberculate or granular; carime distinct; Family Oxydesmid.e, type Oxf/rft's- 

 mus Jiaromarijiitatits, Berlin Museum. 



AXALYTICAL KEY To THE GENERA OF GOMPIIODESMID/E. 



Antennae with ten olfactory cones, arranged in a circle: Genus AsiroHtsmus, type 

 A. stellifer. 

 Antennte with four olfactory cones, as in all other Polydesraoidea 



Sternum of fifteenth segment of male with a broad triangular ensiform i)roces8: 

 Genus Aidodesmus, type A. mossambiciis, Berlin Museum. 

 Sternum of fifteenth segment without process 



Repugnatorial pores 11, segments 11 and 14 without pores: (ieuus Marptodeamus, 

 type M. clianleri. 



Repugnatorial pores 13; segments 11 and 14 provided with pores. 



Sterna of fifth and sixth pairs of male legs each with two distinct processes, those 

 of the sixth much larger; genitalia not strongly curved, pluridentate : Genus 

 Hannodcsmiis, type II. niiens, Berlin Museum. 



Sternum of sixth segment with a single conspicuous median process, that of the 

 fifth unarmed; apical portion of the genitalia strongly recurved upon the basal and 

 produced into a slender flexuous llagellum 



Sternal process of sixth segment of male narrow, bidentate; sternum of sixteenth 

 segment with an abrupt verruciform process on the middle of the anterior edge, 

 directed ventrad: Genus Tycodesmns, type T. medins, Berlin Museum. 



Sternal process of sixth segment of nuiles broad, unidentate; sternum of sixteenth 

 segment unmodified 



Body large, 60-70 mm. ; preaual scale with setiferous tubercles greatly enlarged 

 in both sexes, much exceeding the median angle; sterna of seventh and eighth seg- 

 ments of males with a distinct flattened process at the base of each leg of the pos- 

 terior pair: Genus Gomphodesmns, type G. castaneus, Berlin Museum. 



Body small, 20 mm. ; preanal scale with median angle much more prominent than 

 the setiferous tubercles; sterna of seventh and eighth legs without process: Genus 

 Sphenodesmus, type S. rugulosus, Berlin Museum. 



ASTRODESMUS/ new genus. 

 Euriidesmus pro parte, of Peters, GerstXcker, and Karscit, not of Saussure. 

 Diagnosis. — Body very laige. 

 Aiitenuie with ten olfactory cones. 

 Segments dorsally smootli. 



Lateral carinjie medium, margins thickened, entire. 

 Kepugnatorial pores 1.'5, dorsal on the thickened margins of segments 

 o, 7, 9-19. 



Penultimate segment very short, surpassed by segment 18. 

 Last segment very short, triangular, the apex narrow. 

 Sterna with transverse medianly interrupted ridges. 

 Sternum of segment G of male with a large process. 



' The name alludes to the peculiar conformation of the apical joint of the antenna. 



