T. Davidson — Tertiary Brachiopoda. 405 



' 36. Megerlia ohlita (Michelotti), PL XXL, Fig. 3, OrtJds ohlita 

 (Michelotti), Fossiles des Terrains Miocenes de I'ltalie Septentrionale 

 p. 78, pL 2, fig. 3. 



I am very doubtful whether this so-termed species be distinct from 

 M. truncata, but as Sig. Michelotti seems to be so strongly impressed 

 with the idea that it possesses differences of specific value, I will 

 provisionally record it under its distinctive appellation. I have not 

 myself seen more of it than a ventral valve, and consequently must 

 not pronounce a decided opinion upon the subject. Its surface, 

 according to Sig. Michelotti, would be smooth and marked by con- 

 centric lines of growth only. It occurs in the Middle Miocene of 

 the Hill of Turin. 



37. Megerlia {?) orbicularis (Meneghini), M.S., PL XXL, Fig. 4, 4:a. 

 Shell small, circular, about as wide as long; dorsal valve most 



convex at the umbo, gently concave towards the front; ventral valve 

 uniformly convex, beak incurved, foramen large. Surface marked 

 with numerous thread-like stride. Interior not known. Length and 

 breadth about five lines. Two examples of this small shell were 

 found by Sig. Meneghini in the Upper Miocene of St. Dalmazio 

 (near the Pomarane), and at Palazzo, near Siena. I have not seen 

 the shell but several very fine drawings of it were kindly forwarded 

 to me by the distinguished palaeontologist above named. I should 

 not be surprised if M. ohlita and M. orbicularis were varieties only 

 of M. truncata. 



38. Platidia (Morrisia) anomioides (Scacchi Sp.), PL XXL, Fig. 

 15. Ortliis anomioides (Scacchi and Philippi). Enum. Moll. SiciL, 

 vol. 2, p. 69, 1844:. Platidia anomioides (Costa). Fauna del regno 

 di Napoli, p. 48, pL iii., fig. 4, and pi. iii bis., fig. 6, 1852. 



This well-known species occurs fossil in the Lower Pliocene in 

 various localities near Messina, and is found alive in the Mediter- 

 ranean. Mr. Jeffreys dredged one or two large examples between 

 Shetland and the Fgeroe Islands (Porcupine Expedition, 1869). It 

 had also received the name of appressa from E. Forbes. 



39. Platidia (Morrisia) Davidsoni (Deslongchamps), PL XXL, 

 Fig. 16. Morrisia Davidsoni (DesL). Annals and Mag. of Nat. 

 Hist., second series, vol. 16, pi. x., fig. 20, 1855. 



Some examples of this species were found by Sig. Sequenza in the 

 Quaternary deposits of Trapani in Sicily, and it is found alive in the 

 Mediterranean. 



40. Argiope decoUata (Chemnitz. Sp.), PL XXI, Fig. 5, 5a, and 

 6, 7, 8. ? 



This is a very variable species and seems to have enjoyed a con- 

 siderable vertical as well as horizontal range. Its first appearance 

 (if we correctly identify some small specimens, PL XXL, Fig. 6, 7, 8, 

 found by M. Bay an) would take place in the lower part of his 

 Eocene stage F. This same shell was also found by Sig. Michelotti 

 in the Lower Miocene of St. Liberta in the Vicentin territory. It 

 occurs in the Middle Miocene of the Hill of Turin, and is not rare 

 in beds of the same epoch in Tuscany. It was found along with 

 Crania abnormis, in a sand near the Hospital of St. Colombano, a 



