44 
suggested reference to the Aviculidae rather than Stoliczka’s to the Tridacindae. 
Three species were recorded, all Australian — E. glohosuw, Dana, A/, ellipticum, 
Dana, E. cordutum, Morrisd 
The priucij^al structural features noticed hy Waagen in these Indian 
forms were ; — 
(a) The inequality of the valves, already detected hy Dana, the right 
being the larger. 
(/v) The absence of the gaping lunette suggested hy Stoliczka. 
(c) The existence of “ a little wing projecting from the left valve and 
fitting into a rounded emargination of the right valve.” 
(d) A narrow byssal sinus extending “ from the apex of the right valve 
down to the cardinal margin just in front of the emargination . 
. . . and in front of the large tooth that exists in this valve.” 
(e) Byssal sinus confined to the right valve (Morris’ description gave 
the impression that such a sinus existed in both valves). 
(/) Morris’ reference to the Aviculidae, rather than that of Stoliczka to 
the Tridacnidoe, is probably the more correct. 
(g) Disposition of the muscular impressions like that of MHeo grina . 
(//) The affinities to the Aviculidae consist of (c), {a), and {g). 
1891. — Dr. F. Freeh, in a Monograph on the Devonian Aviculidae of 
Germany, included remarks on various extra- Kuropean genera. Amongst 
these was Eurydesma, described under the name of Leioniyalma^ as a 
suhgenus of Myalii'ia, De Kon. The former is said to differ from the latter in 
the possession of a broad, smooth, fiat surface in both valves below the 
cartilage areas, and under the left umbo “ a tooth-like swelling ” (zahnartiger 
wulst). The shells are large, thick-tested, and occupy a position between 
MyaHna and Perna, the form reminding Dr. Freeh of that of Aphanaia, 
De Kon. The specimen is in the Royal Museum of Natural History, Berlin, 
and is said to have come from Kilama,^ New South Wales. Dr. Freeh 
remarks that other species of Leiomyaliua were described hy Dana as 
Eurydesma, from Harper’s Hill — E. ellipticum, Dana, is a Cardiomorplia,h\\i 
* Waagen — Salt Range Fossils (Pal. Indica), IV, Pt. 2, 1891, pp. 137-43. 
^ Freeh — Die Devonischen Aviouliden Deutschlands. Ahhandl. Geol. Specialkarle Preuss. Thiiring. Staaten, 
1891, IX, Heft 3, p. 201. 
’ Possibly Kiania, Illawarra District — Marine beds near Kiania belong to the Upper Marine Series. 
