104 Mr, H. W. Bates on the Longicorn Coleoptera 



vague group standing in collections under the yet uncharacterized 

 name of Amniscus, Dejean, comprises others which might con- 

 veniently bear this title, as they differ in many respects from 

 the types of Leptostylus. These have an elongated and sub- 

 depressed form, with the basal joint of the posterior tarsi equal 

 to the two following united. They form a connecting link be- 

 tween Leptostylus and Alcidion, differing from the latter in having 

 the elytra oblong without prominent shoulders, instead of the 

 triangular form, broad and elevated at the base, which so well 

 distinguishes Alcidion. The thorax is tubercular on the disk, 

 as in Leptostylus, and its sides are simply prominent in the 

 middle, without acute or spiniform lateral tubercles. The elytra 

 are briefly truncated or rounded at the apex. The thighs are 

 abruptly clavate. In the only species which I have been able 

 to examine closely, the apical segment of the abdomen is conical 

 and somewhat produced in both sexes; but in the male both 

 dorsal and ventral segments are truncated or slightly emarginated 

 at the tip, whilst in the female the dorsal segment is obtusely 

 pointed. 



Alcidion polyrhaphoides of White (Cat. Long. Col. Brit. Mas. 

 p. 394, pi. 10. f. 6) may be cited as the type of the genus Am- 

 niscus as here defined. In this and the species I have to de- 

 scribe the basal joint of the antennae is abruptly clavate near the 

 tip ; but it is doubtful whether this will prove to be a generic 

 character, as some species of Alcidion also have the same feature, 

 whilst their nearest allied species have the joint of the same 

 shape as the generality of the Acanthocinitse. The joint, al- 

 though abruptly clavate, is of the same relative length as in the 

 rest of the allied genera, and it presents also, near the tip on 

 the underside, the small dentiform process which is characteristic 

 of the subtribe. 



Amniscus. pictipes, n. sp. 



A. oblongus, testaceo-rufus, nigro canoque variegatus : thoracis 

 dorso trituberculato, tuberculis anticis fortiter elevatis : elytris 

 prope basin bifasciculatis. Long. 3j lin. S $ • 



Head yellowish, spotted with black. Antennae reddish, joints 

 tipped with black; basal joint swollen beneath near the apex, 

 the latter toothed. Thorax with three tubercles in a triangle on 

 the disk, the two anterior very prominent ; lateral tubercles ob- 

 tuse; the colour is brown testaceous, with two black dorsal 

 stripes. Elytra oblong, gradually narrowed from the middle to 

 the tip, which latter is not truncated; the surface is thickly 

 punctured, especially towards the base, and in the place of the 

 centre- basal ridge there is a large pencil of black hairs ; the rest 

 of the surface even; the colour is testaceous brown, with the 



