DR. T. DAVIDSON ON EECENT ERAC'IIIOPOD.A. 153 



on both valves. Dor.sal valve almost flat, and nicsially doprossod ; umbo nolchod by a 

 semicivcnlav foramen. Ventral valve convex, of moderate deptii, hinge-line straight, 

 area small. Beak very slightly incurved, foramen situated under its angular extremity, 

 margined liy narrow deltidial plates. Surface smooth, marked willi concentric lines of 

 growtli. In the interior of the dorsal valve the loop is not reflected. The converging 

 principal lamelhTB are found attached first to the hinge-plate, and then to a small pillar- 

 shaped median vertical septum. Peduncle very short ; animal possessed of sigmoid 

 vertical labial appendages. Length 2 lines, breadth 2 lines. 



TIah. Dredged in the J<lgean Sea by Prof. E. Porbcs, under the names of Terehratula 

 semlmilum, Philippi, and T. appressa, Forbes, at depths varying from 45 to 105 fathoms; in 

 the Bay of Naples (Costa) ; off the Portuguese coast, near the mouth of theTagus, attached 

 to corals (W. S. Kent); Bay of Biscay and Sahara (' Travailleur ' Expedition), in 178 to 347 

 fathoms ; North of Stornoway (' Knight Errant ' cruise) ; off Cuba and AVest Indies 

 ('Blake' Expedition), 88 to 615 fathoms; off Marion Island in 500 fathoms, and off 

 Prince Edward's Island close to Marion Island (' Challenger ' Expedition). Mr. W. H. 

 Dall records it from San Diego, California, and from Lodos, Santos Bay, south of the 

 United- States boundary in Lower California (Mexico). 



It occurs in the fossil state in the Upper Pliocene rocks of Sicily. 



Obs. As the specific name anomioides is now in general use, I do not feel inclined to 

 disturb it, although those of seiniimlnm and of appressa, Eorbes, seem to have priority. 

 Forbes neither described nor figured his species, and therefore it cannot be said to have 

 been published. The name anomioides is attributed to Scacchi, but he has neither 

 named, described, nor published it. It was a MS. name known to Philippi and to Costa, 

 and they both described and figured a shell in 1844 and 1852 under the name of Orthis 

 anomioides. As the Terehratula semiimlitm, Philippi, is evidently identical with the 

 so-termed Orthis anomioides, and was described and figured in 183G, the specific name 

 seminulum should in reality obtain priority over that given to the shell in MS. by Scacchi. 

 In May 1852 I proposed for T. seminulum anA. similar shells the generic name of Morrisia, 

 not being aware at the time that Costa on the 27th of January of the same year had 

 proposed that of Vlalijdia for the same shell. 



The animal of this interesting and well-marked genus and species has not yet been 

 anatomically examined. The arrangements of its labial appendages are very remarkable. 

 They were briefly described and figured by Costa and by myself in 1852, but more particu- 

 larly by E. Deslongchamps in 1804, in his valuable memoir, ' Recherches sur I'Organi- 

 sation du Manteau chez Ics Brachiopodes articules.' His observations were, however, 

 like my own, nnfortunately founded on dried specimens. He states that the brachial 

 appendages are much more simple than in other genera of the Brachiopoda, and that 

 the two principal branches which lie close to each other at their origin and deviate by 

 a curve towards the centre of the shell, and, having made almost a complete circle, return 

 close to their origin, without forming a spiral. His most imponant observations, how- 

 ever, relate to the mantle, which he states to be so thickly coated with spicula that it is 

 impossible to separate it from the brachial appendages without injuring them; that 



