18 Mr. T. V. WoUastou on the Colcoptcra of St. Helena. 



tory motions, had tlien become sedentary, and lay moored to 

 a rocky surface, or was partially buried in its sandy matrix ; 

 in such a position its upper or nuire exposed surface consisted 

 of the posteal half of the area ; and this portion, either exposed 

 or discovered by the motion of the excurrent and incurrent 

 siphons, invariably became a prey to the marine Hosh-eaters : 

 a j)ortion more or less lar^e is always found broken away and 

 removed. The whole general aspect of the adult valves ex- 

 hibits that worn or abraded condition with which we are also 

 familiar in Byssoarca, and doubtless resulted from similar 

 causes in both instances, 



I hope to present faithfully executed fig'ures of this byssi- 

 ferous Trigoaia in a Monograph on the British Trigonias, 

 now in preparation for the Palaiontographical Society. 



IV. — On the Coleoptera of St. Helena. 

 By T. Vernon Wollaston, M.A., F.L.S. 



[Concluded from vol. iv. p. 417.] 



Fam. 19. Anthribidae. 



(Subfam. ARuEOCERIDES. 



Linea transversa prothoracica basthn's, marginem ipsum ba- 



salem elevatum efficiens.) 



Genus 35. Ar^ocerus. 

 Schonherr, Cure. Disp. Meth. 40 [script. Araecerus] (1826). 



52. Aneocerus fascicidattis*. 



A. breviter ovalis, crassus, brunueo-piceu.s, pxibe brevi squamsefomii 

 demissa cinerea grisea(iuc vestitus nccnon in olytris plus minus 

 obsoletissime (sc. in interstitiis altoriiis) longitudinalitcr tessel- 

 latus ; capite prothoraceque (subter pube) opacis, densissime et 

 rugose punctatis, illo in medio tenuiter carinulato oculis maximis 

 prominentibus, hoc subconico, postice lato bisinuato, costa trans- 

 versa in marginem basalem coeunte nccnon utrinque marginem 

 lateralem (us(jue ad medium lateris ductum) cfficiente, angulis 

 posticis subrectis ; clytris apice tnincato-rotundatis, (subter pube) 

 subopacis, densissime et rugose granulatis ac leviter crenulato- 

 striatis ; antennis pcdibusque elongatis et (pra;cipue illis) graci- 

 libus, illis rufo-testaceis clava obscuriore, his rufo-ferrugineis, 

 tarsorum art" l'"" longissimo. 



Long. corp. lin. 2-2^. 



Cunidio fascinilatus, DeGeer, Ins. v. 27G, t, 10. f. 2 (1775). 

 Anthribus coffea, Fab., Syst. Eleuth. ii. 411 (1801). 



Two examples of an Arceoceriis^ which were taken at St. 

 Helena by Mr. Melliss, I feel almost confident arc referable to 

 the A. fasciculatus (which is usually known in collections as 

 the coffea- of Fabricius\ though 1 have thought it desirable to 



