DR. T. DAYIDSOX OX EECEXT BRACHIOPODA. 189 



Orbicula turhinata, Dcsliayes, ed. Lamarckj An. sans Vert. vol. vii. ji. 317, 1836. 



Crania rim/ens, .Vnton, Verz. der Conchylien, p. 2\, 1839; G. Sow. Thcs. Conch, i. p. 307, ])1. Ixxii. 

 figs. 10 & 11, 18 Ifi ; E. Forbes, Report ou the Mollusca of the ,Egeau Sea, Brit. Assoc, for the Advance- 

 ment of Science, 1843. 



Crania ringens and C. roslrata, E. Suess, Ueber die "Wohnsitze der Brachiopoden, Sit^ungsb. k. Akad. 

 Wissensch. AVien, Bd. xxxvii. p. 2:23, 1859. 



Crania rostrata, L. Reeve, Conch. Icon., Monogr. of Crania, pi. i. fig. 3, 1862. 



Crania rinyens and C. rostrata, Goldfuss, Petrefaktenk. Deutschlands, p. 291, and p. 292, pi. cL^ii. 

 figs. 2 & 3, 1826-33; Brusina, Moll. Dalmati, Rcale Soc. Botanica di Vienna, vol. xvi., 1866. 



Crania turhinata, L. Reeve, Conch. Icon., Monogr. of Crania, pi. i. fii;-. 1, 1802 ; II. C. A\'cinkaufiF, Die 

 Conch, des Mittclnieeres, p. 291, 1867. 



Crania anomala, var. turhinata, Dall, Revision of the Craniidaj and Discinidic, Bull. AIus. Comp. ZoiJl. 

 Harvard, vol. iii. p. 34, 1871 ; and Proc. Acad. Nat. Sci. Philadelphia, p. 199, 1873. 



Crania rostrata, L. Jouhin, Comptcs Reudus, t. xcix. p. 98j, 1884; t. c. p. 464, 1885; Arch, dc 

 Zool. Exper. t. iv. p. 161, 1886. 



Shell marginally more or loss rounded, rather Avider than long, In'oadest anteriorly, 

 sliglitly indented at its posterior and anterior margins; lal)ial margins outwardly curved 

 and slightly pinched in close to the posterior margin. Upper valve more or less sub- 

 trapezoid, conical or limpet-like. Vertex central or suhmarginal, pointed or hooked, 

 curving towards the posterior margin, valve flattened from the apex to the posterior and 

 often anterior margins. Smaller or lower valve moulding itself to main objects by its 

 entire outward surface. Upper valve small or roughened. In the interior of the flat- 

 tened lower valve a Avide, thickened, sloping, granulated rim or border, thin at the edge, 

 surrounds the shell; it forms a slight inward curve posteriorly, then curves in just 

 under the posterior angles and again outwardly all round the anterior portion of the shell. 

 Each of the posterior angles of the inner margin is taken up by a projecting circular scar, 

 left by the divaricator muscle. These two scars are widely separated, and the intervening 

 space is occupied by two other small projecting eminences, which Hancock refers to 

 mesenteric muscles, destined probably to draw the alimentary tube backward. At the 

 anterior labial angles of the divaricator scars another smaller one is seen, AAhich has been 

 attributed by the same distinguished zoologist to the dorsal adjustors. Lower down 

 towards the middle of the bottom of tlie valve are two oblique, almost contiguous oval- 

 shaped scars, which have been referred to the adductor muscles, and between them and 

 more towards the posterior edge is seen a nose-like projection composed of two small 

 oblique oval-shaped scars, which have been referred to the anterior extremities of the 

 dorsal adjustors. The remaining anterior portion of the interior of the valve is traversed 

 by digitate vascular (?) impressions. In the interior of the upper valve a raised thick- 

 ened rim or border margins the interior of the shell and follows the ins and outs or 

 curves of the lower valve. At the inner angles are two oblique oval-shaped scars due to 

 the divaricator muscles, and in the space separating them are two other smaller scars, 

 perhaps due to the mesenteric muscles ; under these and lower down are two large 

 oblique projecting elevations caused by the adductors, these impressions being separated 

 from each other by a narrow hollow space, the remaining area between these and the rim 

 being taken up by digitate vascular (?) imjiressions. The shape and position of tlie 

 labial appendages have been described under Crania anomala and need not here be 

 repeated. Colour light yellow or light brown. Length G lines, breadth 7 lines. 



