llO Froceedings of tlte Royal Society of Victoria. 



umbos being situated further back from the anterior, and its 

 consequent larger development of the anterior portion of the 

 shell ; it also differs in the position and characters of the cartilage 

 plate, and transverse ossicle, and in its proportional height being 

 less. 



Family Mksodesmatidae. 



Genus Mesodesma, Deshayes, 1830. 



Mesodesma erycinaea, Lamarck. 



1819. Crassatella erycinaea, Lamarck. Anim. S. Vert., 



vol. vi., p. 134, No. 9. 

 1835. Mesodesma erycina, Quoy and Gaimard. Astrolabe 



ZooL, vol. iii., p. 507, pi. 82, f. 1, 2, 3, 4. 

 1835. Mesodesma diemenense, Quoy and Gaimard. Id.., 



p. 507, pi. 82, f. 12-14. 

 1839. Crassatella erycinaea, Lamarck. Anim. S. Vert. 



(3rd. ed. Deshayes and Edwards), vol. ii., p. 



539, No. 9. 



1841. Crassatella erycina, Delessert. Recueil de Coq., pi. 



4, f. 4.7, l>, c. 



1842. Mesodesma erycina, Hanley. Cat. Rec. Biv. Shells, 



p. 38. 

 1854. Mesodesma erycinaea. Reeve. Conch. Icon., vol. 



viii., pi. 2, f. 12. 

 1856. Mesodesma erycinaeum, Hanley. Cat. Rec. Biv. 

 Shells, p. 341, pi. 12, f. 26, and in explanation 

 of plate M. erycinea. 

 Hab. — Port Albert. Alive in sand bank, Mentone, Port 

 Phillip (J. Atkinson). 



Mesodesma elongata, Deshayes. 



1854. Mesodesma elongata, Deshayes. P.Z.S. Lond., p. 



337, No. 94. 

 1854. Mesodesma elongata. Reeve. Conch. Icon., vol. 



viii., pi. 1, f. 5. 

 1897. Mesodesma elongata, Tate. T.R.S. S.A., vol. xxi., 

 pt. 1, p. 46. 

 Hab. — San Remo, Airey's Inlet, Apollo Bay. 



