﻿X Y L P n A G A. 



Genus XYLOPHAGA. Tarhm. 



MoLLUSCl'M TKREBEANS, verwiforme, siphonibtis ad 



tenmmun divisis. Testa hivalvis glubosd, antice 



Idlinr^inw aiigulatim apertd, pustice fere clausd, 



mri}io sulco lata divisd, cardine edcntulo, calloso. 



Tnhd mdld. 



BoiUNC. WOUM-SHAPED jroLUSC, with siphons divided 



at the end. Shell bivalve, globose, anteriorly 



very widely angnlai-ly open, posteriorly nearly 



closed, divided in the middle with a wide groove ; 



hinge with no teeth, callous. No tube. 



Xylophag® ai-e found in floating wood, gcnei'ally 



boring across the grain and not with it, as in the case 



of Teredo. Only two species are known ; one Briti.sh 



and Boreal, the other collected by Mr. Cuming at 



Vaiparai-so. 



Species 1. (Mus. Sowerby.) 



XYLOiitiGA DORSALIS. Xijl. tcdd gloho.id, epidermide 

 teiiui aurantio-vindi indiitd, medio sulco piano 

 costis duabiis marginato divisd; latere aniico 

 brcvi, validissimd angulafo ; latere postico brevith- 

 cido, niargine dorsali elevato ; laininis accessoribtui 

 trigonis, latitudiae lunjiladiiiom siiperante. 



Tlii: DiiKSAL XTi.ni'iiA.i.\. Sliellglobo.se, covered with 

 an orange-green epidermis, divided in the middle 

 by a flat groove bordered by two ribs ; anterior 

 side short, very strongly angular ; posterior side 

 rather short, with dorsal margin raised, accessory 

 plates trigonal, broader than long. 



TiuiON. British Bivalves, II. Pig. 45. 



Species -1. (Fig. a, h. Mus. Brit.) 



XYLOPUA(iA GLOItOSA. Xijl. lesid laliiiscn la. latere am 

 moderat'e angulafo ; latere postico producfo, i,i 

 gine dorsali declivi ; lamiHi-' acccssoril,Ns ,,„. 

 lati^, longitiuUne latitude,, m ■.■ii/.rnuihluis. 



The GLolioSE Xylomu.-.a. ,^h,ll rather brniul, : 

 terior side moderately angular; |Kisten(ir s 

 produced, dorsal margin slo])ecl ; uccessi 

 plates claw-shaped, longer than broad. 



SowEBHY. Proc. Zool. Soe. 1834; Thes. Coneh. ! 

 10, p. 50;5. 



Hab. Valparaiso. 



The shell is wider and the posterior dorsal mart 

 more sloped than in X. dorsalis. The proportions 

 the accessory plates are reversed. 



NAVE A. 



Genus XAVEA. Gray. 



Testa ovata, antice lath arcualim Jiians, poslice clo.usa, 

 margine siiperiori hiatus antice laniind retlexd 

 marginato. 



Shell ovate, anteriorly broadly gaping in an arch, 

 posteriorly closed, upper margin of the anterior 

 hiatus bordered by a reflected lamina. 



Spe 



(Fig. 3, Mus. Brit.) 



I have not seen any species of this genus but the | 

 following one, which seems to perforate the sponges I Gi;ay. MS. i 

 in which it is found embedded. LLab. ? 



Natea subgloboSA. Nav. testa medio sidcu dicisd : 

 latere postico brevi. rotuado ; latere aniico, hiata 

 r.iaximo, supemh ad marginem utrinquc cuiwato 

 et nrflexo. 



The sduglobose Navea. Shell divided by a groove 

 in the middle ; posterior side short, rounded : 

 anterior side with a very largo hiatus, reflected 

 and cunoate at the margin above. 

 Brit. Mus. 



