TRIBE BRACHTOPODA. 329 



sometimes very obsolete, sometimes very large, particularly those 

 which form the sides of the mesial furrow. Var. T. Recurva, Quoy, 

 Ast. — Sow. Th. 1, p. 350, t. 69,/. 34, 5, 6. Rounded-subtetragonal ; 

 edge undulated, flexuous at the sides dorsally ; mesial ridge obsolete ; 

 lower valve broader than long. 1£. Australia. l 



T. Grayii. Davids. Z. P. 1852, t. 14,/. 1, 2, 3.— Waldheimia G. 

 Gray, Brack, p. 79. Suborbicular, reddish yellow, becoming deep 

 red at the lines of growth, radiated with numerous unequal bifur- 

 cated and intercalated ribs ; upper valve convex ; lower valve flattish ; 

 beak obtuse, with distinct lateral ridges ; perforation very large, in- 

 complete; deltidia disunited; loop elongated, reflected. l-i-...l£. 

 Korea. 



T. Caput-serpentis.* — Anomia C. Retusa and Pubescens, Lin. 

 — T. R. Retz. — A. C. Ch. 11, /. 2013.— W. t. 11, /. 22.— T. C. 

 Lam.— Sow. G.—Phil. 95.— Sow. Th. I, p. 343, t. 68,/. 1 to 4, and 

 t. 72, /. 116.— Br. Mol. 2, p. 353, t. 56, /. 1, 2, 3, 4.— T. Costata, 

 Lowe, Z. J. 2. — T. Aurita, Flem. — Tereeratulina C. Gray, Brack. 

 p. 49. Ovate, of a rounded somewhat pentagonal figure, whitish ; 

 valves nearly equally convex, with radiating dichotomous subgranular 

 costellse ; margin minutely crenulated, flexuous at the sides, slightly 

 notched ventrally. Upper valve somewhat beaked, its perforation 

 moderate, oblique, incomplete ; hinge-area rather flattened, deltidia 

 nearly obsolete ; internal appendage small, about one-third the length 

 of the shell, arched below, and vaulted, f. Europe.* 



T. Septentrionalis. Contkouy, Bost. J. 2. — Sow. Th. 1, p. 344, 

 t. 68, /. 7, 8. — T. Caput-serpentis, Gould, Mas. 141. — Terebra- 

 tulina S. Gray, Brack, p. 50. Subovate, obtusely acuminated dor- 

 sally, nearly white ; valves almost equally convex, with very slender, 

 dichotomous radiating roughish little ridges ; margin minutely crenu- 

 lated, flexuous at the sides, nearly straight ventrally, perforation 

 rather large, not complete, somewhat oblique; hinge-area nearly 

 flattened, with small nearly obsolete deltidia; internal appendages 

 small, two-fifths of the length of the valve, arched ventrally, with a 

 little branch above on each side, joined in the middle, f . U. States. 

 Distinguished from the last by its finer stria, its larger and less oblique 



1 T. Rotundata, Lam. 5. — E. t. 239,/. 5. "Rounded, whitish, 

 smooth (with only very delicate concentric striae) ; ventral edge bipli- 

 cated, contracted on either side." Not since recognised. 



2 This and the six following species belong to Terebratulina. 

 " Finely striated, auriculate ; deltidium usually rudimental ; foramen 

 incomplete ; loop short, rendered annular in the adult by the union 

 of the oral processes." 



2 b 



