404 T. Davidson — Tertiary Brachiopoda. 



In external shape this small species mucli resembles T. minor, but 

 its interior is so dissimilar to it, as well as to that of Waldheimia, that 

 Sig. Sequenza seems to think that it will be necessary to create a 

 sub-section for its reception. It occurs in the Upper Pliocene of 

 Gravitelli, near Messina. 



33. Waldhei'mia?depressa{Seqvienza,),'Pl.'KIX.,'Fig. 14:. Sicilian 

 Brachiopoda, pi. v. fig. 15, 16. 



This is a very minute shell, to which the same palaeontologist 

 had, in 1862, applied the designation of T.pusilla. Sig. Sequenza has 

 recently informed me that it will be perhaps necessary to suppress it 

 entirely. I have never seen the shell, nor do I believe Sig. Sequenza 

 has ever seen its loop. It occurs in the older Pliocene of Eometta, 

 near Messina, where the shell appears to be very rare. 



34. Terehratella septata (Philippi), PI. XIX., fig. 9, 10. Enum. 

 Moll. Sicilige, vol. 2, p. 68, tab. xviii., fig. 7, 1844. 



This shell has been well described by Philippi and Sequenza. In 

 external shape it does not seem to differ very much from W. septigera, 

 but has its beak more incurved and its beak ridges sharply defined, 

 a character not present in the last named species. The loop in T. 

 septata is undoubtedly that of a Terehratella (PL XIX., Fig. 10) 

 while that of W. septigera would agree with that of Waldheimia. It 

 occurs in the older and newer Pliocene of Lamato and Nasiti in 

 Calabria, and abounds likewise in several localities near Messina. 



35. Terehratella ? Spinellii (Meneghini), M.S. PI. XIX., Fig. 17. 

 Shell longitudinally oval, sides and front rounded, valves almost 



gibbous and uniformily convex without fold or sinus ; beak small 

 and truncated by a circular foramen ; each valve is ornamented 

 with about 22 small rounded simple ribs. Interior not known, but 

 on the exterior of the dorsal valve a dark line extends from the umbo 

 to about half the length of the valve, indicating the presence of an 

 internal septum, which may possibly have afibrded a second attach- 

 ment to the loop. Length 7, width 5^, depth 5 lines. 



A single specimen of this shell was obtained by Sig. Meneghini in 

 the volcanic tuffas of the Nummulitic or Eocene formation at 

 Chiampo in the Vicentin. It bears much outward resemblance to some 

 small specimens of Terehratella ohJonga, but is a more inflated shell. 



36. Megerlia truncata (Linne), Plate XXI., Fig. 1, 2. 



This is a well known but very variable shell, and I fear that 

 more that one so-termed species has been fabricated out of some of its 

 variations. In external shape it is usually more or less semi-circular 

 and wider than long, but it is likewise sometimes almost circular, 

 and more or less strongly marked by numerous fine dichotomous 

 thread-like radii, these being scarcely visible on some specimens, 

 while they are more or less distinctly seen on others ; these small ribs 

 are also granulated in some specimens. It evidently existed during 

 the Miocene and Pliocene periods, and is a common shell in the 

 Mediterranean. In the Miocene it occurs at Grangia, in Piedmont, 

 and was found also in the same formation in Tuscany by Sig. 

 Meneghini. It is very common in the older and newer Pliocene of 

 Calabria and Sicily, nor is it a rare fossil in the Island of Malta, at 

 Nice, Gibraltar, and in many other places. 



