124 DE. T. DAVIDSON ON EECENT BRACHIOPODA. 



by its colour, the last-named species beinsj rather more triangular in form and marked 

 with deep crimson rays. Krcmssina Lamarckiana is also a much smaller species than 

 Kraussina pisum. At p. 33 of his ' Siidafrikanischen Mollusken,' Dr. F. Krauss expresses 

 the opinion that the Terehratula Algoensis of Sowerby is a synonym of the species under 

 description : this is very probably the case, and not of K. rubra as was supposed by Lovell 

 B-eeve. 



73. Keaussina (Megeklina) Lamakckiana, Davidson. (Plate XXI. figs. 7-11.) 



• 



Kraussia Lamarckiana, Davidson, Proc. Zool. Soc. 1852, p. 80, pi. xiv. figs. 23, 23; Ann. & Mag. 

 Nat. Hist. 2nd ser. vol. ix. p. 370, 1852; lutr. to vol. i. of Brit. Foss. Brach. p. 69, 1853; Woodward 

 & Gray, Cat. of Brachiopoda in the British Museum, p. Ill, 1853; H. & A. Adams, The Genera of 

 Recent Mollusca, vol. ii. p. 579, 1858; S. P. Woodward, A Manual of Mollusca, p. 218, fig. 120, 1858. 



Kraussina Lamarckiana, E. Suess, Ueber die Wohnsitze der Brachiopoden, Sitzungb. k. Akad. der 

 Wissensch. Wien, Bd. xxxvii. p. 21], 1859. 



Terehratula {Kraussia) Lamarckiana, Lovell Reeve, Conch. Icon., Monogr. Ter. pi. ix. fig. 34', 1861 ; 

 Ann. & Mag. Nat. Hist. 3rd ser. vol. vii. p. 182, 1861. 



Kraussina Lamarckiana, Chemnitz, Man. de Conch, vol. ii. p. 206, fig. 1057, 1862; Dall, Amer. 

 Journ. of Conch, vol. vi. p. 139, 1870; Proc. Acad. Nat. Sci. Philadelphia, 1873, p. 190; Hutton, Cat. 

 of the Marine Mollusca of New Zealand ; Tenison Woods, Census of the Marine Shells of Tasmania, Proc. 

 Roy. Soc. of Tasmania, p. 34, 1877; Davidson, Report on the Brachiopoda, Voyage of H.M.S. 'Chal- 

 lenger,' Zool. vol. i. p. 53, pi. iv. fig. 9, 1880. 



Megerlina Lamarckiana, E. Deslongchamps, Etudes critiques sur des Brachiopodes nouveaux ou peu 

 connus, p. 159, pi. xix. fig. 11, 1884. 



Shell small, somewhat subquadri lateral, about as wide as long, flexuous, fulvous 

 white or light brown. Dorsal valve slightly convex, with a rather deep longi- 

 tudinal mesial depression. Hinge-line straight, and rounded at its angles. Ventral 

 valve deeper and more convex than the dorsal one, longitudinally keeled along the 

 middle. Beak slightly incurved, and truncated by a large incomplete foramen, laterally 

 margined by two rudimentary deltidial plates ; beak-ridges sharply defined, leaving a 

 false areal space l)etween them and the hinge-line. Surface of both valves ornamented 

 by a number of small radiating costse, increasing in number by the interpolation of 

 shorter ribs. Length 4 lines, breadth 4i lines, depth 2 lines. 



In the interior of the dorsal valve the hinge-plate is wide and concave, with two eye- 

 shaped rudimentary scars between its outer margins. Under the middle of this plate a 

 slightly raised mesial septum, thickened, and most elevated near its anterior extremity, 

 extends to less than half the length of the shell ; close to its anterior extremity arise two 

 deviating, ^ -shaped, broad lamellae, slightly expanded and curved at their extremities ; 

 under these, on each side of the septum, are attached two slightly projecting, wide, 

 curved rudimentary lamellae, which simulate the part of the principal lamella? attached, 

 in other genera, to the sides of the septum. The bottom of the valve is costated and 

 faintly tuberculated ; a row of short, erect spine-like asperities rising perpendicularly 

 close to and all round the inner margin. Brachial appendages small, the central lobe 

 being the least. Shell perforated by small canals. 



Sab. Dredged in great abundance by Mr. Brazier in Double Bay, Port Jackson, New 



