356 ANODONTA. 



TJniO jolinstoni, Etheridge, jun. 



1881. Unie johnstoni, E. Etheridge, jim., Pap. Roy. Soe. Tas. 1880, p. 20, 

 plate, two upper figures. 



1887. Unio johnstoni, Tate, Trans. Roy. Soc. South Aust. vol. ix. p. 153. 



1888. Unto johnstoni, Johnston, Geol. Tasmania, pi. sxxiv. figs. 1-la. 



The author states that this does not resemble any of the living 

 Australian species, but approaches nearest to U. mutahilis, Lea, 

 found in the neighbourhood of Brisbane. The condition of the 

 specimens, which are in the state of ironstone casts, renders it 

 impossible to describe the features of the hinge-line or the surface 

 characteristics, so that even the generic reference is a little doubtful. 



Dimensions. — Height 51 mm. ; length 99 mm. 



Form, and Loc. — " Tertiary " : Tasmania. 



96928. Several double-valved specimens, including the type 

 figured {op. supra cit.) by Mr. Eobert Etheridge, jun. ; from the 

 Tamar river, between Whirlpool Reach and George Town. 



Presented ly Br. J. Milligan. 



98219. Six specimens ; from Launceston. Purchased. 



L. 6099. Two casts of the adult ; locality (?). Purchased. 



Genus ANODONTA, Lamarck. 

 [Mem. Soc. Hist. Nat. Paris, 1799, p. 87.] 



Shell inequilateral ; umbones small ; cardinal border long, eden- 

 tulous, but giving indications of a horizontal ridge which represents 

 the posterior lateral tooth of Unio ; ligament exterior ; scars of 

 the adductors of the valves not deep ; impression of the anterior 

 adductor of the foot small, near that of the valves ; scar of the 

 posterior adductor of the foot practically confluent with that of 

 the adductor of the valves in the same region ; a muscle-scar also 

 in the umbonal cavity ; impression caused by the attachment of 

 the visceral mass well marked. 



Type. — Mytilus cygnetis, Linnasus. 



Anodonta tamarensis, Etheridge, jun. 



1881. Anodonta (?) tamarensis, R. Etheridge, jun., Pap. Roy. Soc. Tas. 

 1880, p. 22, plate, two lower figures. 



1887. Tlnio tamarensis, Tate, Trans. Roy. Soc. South Aust. vol. ix. p. 153. 



1888. Anodonta tasmanica, Johnston, Geol. Tasmania, pi. xxxiv. figs. 2-2a. 



