386 On the Arrangement of the Pholadidse into Natural Groups. 



like former, but according to the figure shorter in front, and 

 longer and more rounded behind. Spengler, in his description 

 and figure, appears to mistake the front for the hinder part of 

 the shell. 



C. Dorsal muscle only covered with a coriaceous epidermis. The 

 cavity which the animal inhabits lined with a regular shelly 

 tube which surrounds the valves. Teredinina. 



12. Teredo, Linn. Teredo u, Blainv. Malleolus, Gray. 



* Tube concamerated near the external opening. 



1. T. Norvagicus, Spengler. T. nigra, Blainv. T. Bruguieri, 



Chiaje. T. Norvegicus, Thompson. 



2. T. denticulata, Gray. T. navalis, Moller, Moll. Green. Green- 



land. 



** Tubes not chambered near the outer opening. 



3. T. batavus, Spengler. T. navalis, Blainv. 



4. T. nana, Turton. T. navalis, Milne-Edw. T. megotara, Forbes 



and Hanley. 



5. T. malleolus, Turton. 



13. Xylotrya, Leach MSS. ; Gray, Ann. Phil. 1825. Bankia, 



Gray, 1840. Teredo a, Schum. 1817. Teredo & Blainv. 

 Xylophaga, part., Sow. Man. ! 



1. X. bipalmulata. T. b., Lamk. Syst. T. palmulatus, Lamk. 



Hist. Taret de Pondicherry, Adanson. 



2. X. Stutchburyi, Leach, Blainv, Tered. navalis, Spengler. 



3. X. Philippii. Teredo palmulata, Chiaje, Philippi. 



4. X. carinata. Teredo c, Leach, Blainv. 



5. X. pennatifera. Ter. p., Blainv. T. palmulata, Leach. T. bi- 



pennata, Turton. T. navalis, Home. 



14. Cuphus, Guetard. Kuphus, Gray, 1840. Kyphus, Agassiz. 



Furcella, Oken< Septaria, Lamk. Clausaria, Menke. Clo- 

 i sonaria, Ferussac. 



* I 1. C. arenarius. Solen a., Rumph. \epta^a a., Lamk. Serpula 

 4*\ polythalamia, Linn. S. gigantea, Schroet. Teredo gigan- 



' tea, Home. 



15. Guetera, Gray. Fistulana, sp., Lamk. Teredo, sp., Spengler, 



Megerle, Deshayes. 



1. G. corniformis, Gray. Fistulana c, Lamk. 



2. G. clava. Teredo clava, Gmelin. Fistulana gregata, Lamk. 



3. G.?lagenula. Fistulana 1., Lamk.', perhaps same as preceding. 



