43 
lateral surface, as well as form.” Dana’s figure (liis PI. VIII, figs. 1, \a and 
our PI. XXIII, figs. 3 and 4) does not appear to us to he a representation of a 
typical specimen of E. cordata. 
1871 . — Dr. StolicZika gave a full generic description of Eurydemia , 
but differed from Morris in regard to its aflinities. He considered that “ the 
general form, tlie excavated and gaping lunula, the strong development of 
the ligament hehnv the heak, and the presence of a strong cardinal tooth in 
the right valve all tend towards a relation of the genus to Tridncna and 
Ilippopus^'^. An affinity to the latter had already been suggested by Dana. 
1884 .— Mr. G. W. T ryou, Junr., in his “ Structural and Systematic 
Conchology,” reproduced Stoliczka’s description and adopted the placing of 
Eurydesma in the Tridacnidae. 
1887 . — Dr. Paul Eischer placed Eurydesma near Trklacun, assigning 
to it a Devonian age in error. ^ 
1888 . — Eurydesma also occurs in Tasmania, hut was not included in 
Strzelecki’s collections. Mr. 11. M. Johnston records E. sacenlns, McCoy, 
sp., from the Tasmanian Upper Marine Series of the Permo-Carboniferous,® 
and figures several fossils as E. cordata, Morris, from the bower Marine of 
Maria Island, and Bridgewaterk The occurrence of Eurydesma in the 
U})per Marine Series is of interest, and will he referred to later on. 
Of the other shells figured by Johnston more will he said subsequently 
— his Notoni'fa Beddumei appears to he Eurydesma hobarteusis (Syst. Acc., 
PI. XVI, fig. 2), and to the same species may he va'inwed E. cord ala , Johnst., 
non Morris {IbUL, PI. XVII, figs. 2, 3). Notomya GouhU, Johnst. {Ibid., 
PL XVII, fig. 1) is our Eurydesma eordatum, var. sarculum-, and Ids 
Bachydomus globosus, non Shy. {Ibid., PI. XVIII, figs. 1, la), and P. 
Konincki (?) cannot, from the figures, he distinguished from E. eordatum. 
1891 . — Dr. William Waagen detected the presence of Eurydesma, in 
the Permo-Carboniferous of the Salt Range, India, and drew attention to 
points in the structure, which will he referred to later. He supported Morris’ 
' Stoliczka — Cret. Fauna S. India (Pal. Indica), III, Pelecypoda, Pt. 5, 1871, p. 226. 
^ Fischer — Man. Conchyl., 1887, fasc. 11, p. 118."). 
^ .lohnston — Syst. Acc. Geol. Tas., 1888, p. 114. 
‘ Johnston— 0/;. nt., pp. 114, 119, PI. XVII, figs. PI. XVIII, fig. 11), and PI. XIX, figs. 1, la. 
