DE. T. DAVIDSON ON EECENT BEACHIOPODA. 223 



to those already described under Glottidia albkla. Length of sliell 1 inch 8 lines, breadth 

 7 lines ; length of peduncle over 1 inches. 



Mah. At the head of the Gulf of California, on the Lower Californian shore, opposite 

 the mouth of the Colorado River; on sandy shelly mud at low-water mark. Ten 

 specimens of the animal were collected by Dr. Edward Palmer, who spent many hours 

 groping in the mud for the small number of specimens above recorded. 



Ohs. This is the largest species of recent Glottidia hitherto discovered. It was care- 

 fully described by Dall in 1871 as a variety (^) of G. albida, but in 1873 he considered it a 

 distinct species, and I feel inclined to agree with him in his last determination. G. Palmeri 

 is, as stated by Dall, a much more elongated shell than G. albida, and narrowei*. The 

 beaks arc more acute, the internal laminae are closer together, and less widely divergent. 

 The peduncle, ho adds, is much longer, and the brown colour, so conspicuous on the 

 exterior, is not found in G. albida, which also has a much more prominent median 

 carina, and a more solid shell, which does not gape. It is most desirable tliat the animal 

 of this fine species should be anatomically examined. When describing Liagula (or Glot- 

 tidia) Lesueuri from the Silurian rocks of Brittany and Budleigh Salterton, I remarked 

 that it had been questioned by M. de Tromelin whether that species was a true Lingiila. 

 It is characterized by the presence of a median septum on the interior of the ventral 

 valve, and two diverging ones on the dorsal one, and in external shape and character 

 so closely resembles Glottidia Falmerl that were this recent form fossilized, it would be 

 hard to distinguish it from the Lower Silurian li. Lesueuri. 



128. CtLOTtidia Audebarti*, Broderip, sp. (Plate XXVIII. figs. 7-11.) 



Lhiffula Audcbardi, Broderip, Traus. Zool. Soc. vol. i. p. 143, p]. xxiii. fig. 14, 1835 ; Owen, Trans. 

 Zool. Soc. vol. i. p. 157, 1835 ; Kiistcr, ed. Chemnitz, Concli.-Cab. pi. i. fig. 11, 1843; G. B. Sowerby, 

 Concli. Icon. i. p. 338, ^\. Ixvii. fig. 5, 184(3; Anton, Verzeich. d. Conch, p. 24, 1839; Davidson, Ann. 

 & Mag. Nat. Hist. 2nd scr. vol. ix. p. 377, 1852; L. Reeve, Conch. Icon., Monogr. of L'lnyulu, pi. i. fig. 5, 

 1859; E. Suess, Ucber die Wolmsitze der Brachiojioden, Sitzungsb. k. Akad. Wisseuscli. Wien, Bd. 

 xxxvii. p. 230, 1859. 



Lhigula pyrumidatu, Stimpson, Amer. Jouru. Sci. & Arts, vol. xxxix. p. 444, 1860. 



Lingula Audebarti, Deshayes, in Lamarck, An. sans Vert. ed. 1836 ; E. Morse, Amer. Naturalist, 

 vol. iv. p. 314, figs. 76-78, 1870 ; Amer. Jouru. Sci. & Arts, vol. 1. figs. 1, 2, 3, 1870 ; Ou the Systematic 

 Position of the Brachiopoda, Boston Soc. Nat. Hist. vol. xv., 1873. 



Glottidia Audebarti and G. jjyranddata, Dall, Amer. Journ. Concli. vol. clviii., 1870 ; Proc. Acad. Nat. 

 Sci. of Philadelphia, p. 204, 1873. 



Lingida pyramidatu, Davidson, " Brachiopoda," Encyclopiedia Britannica, ix. cd. p. 188, 1876 ; 

 Brooks, On the Development of Lingula, Scientific Results, Chesapeake Zool. Laboratory, p. 35, 1878. 



Lingula {Glottidia) pyramidatu, Davidson, Brit. Poss. Brach. vol. v. pp. 328, 329, 1884; H. G. Beyer, 

 Studies from the Biol. Laboratoiy, Johns Hopkins University, vol. iii. no. 5, March 1886. 



Shell oblong, thin, narrow, broadest posteriorly, beaks tapering to an acutely angular 

 termination. At about one third of its length the margins gradually taper poste- 

 riorly, front margin nearly straight. Valves moderately convex, smooth, marked with 



* The word printed by Broderip '' Audehanlii " was corrected by Deshayes, in his edition of Lamarck, iuto 

 Audibarti, the species being named iu honour of M. J. d'Audebart de Ferussac. 



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