BEACHIOPODA 



269 



Fig. 439 Tere- 

 bratulina septen- 

 trionalis (Tryon). 



A, dorsal aspect ; 



B, inner surface 

 of dorsal shell, 

 showing calcare- 

 ous arms. 



1. TEREBRATULINA D'Orbigny. Shell punctate, with 5 radiating 

 striations; calcareous loop short and forming either a perfect or a 

 broken ring: 8 species; 22 fossil species. 



T. septentrionalis (Couthouy) (Fig. 439). Shell 

 thin and semi-transparent, yellowish or whitish, broadly 

 oval; beak projecting but little, truncated horizontally, 

 with a large orifice; 13 mm. long and 8 mm. broad: 

 coast of New England, in 20 fathoms off Cape Cod, at 

 low-water line farther north; common. 



T. caput-serpentis (L.). Shell oval, whitish or 

 yellowish; 25 mm. long; 17 mm. wide: Europe; Florida 

 and the West Indies (var. cailleti) ; Pacific coast from 

 San Diego to Aleutian islands (var. unginculata) . 



2. WALDHEIMIA King. Shell globose and smooth, 

 calcareous loop composed of 2 slender branches which 

 extend from the hinge almost to the front edge of the 



shell, then curve backwards to the center, where they join: 10 species; 

 90 fossil species. 



W. floridana Pourtales. Shell triangular, gray or 

 brownish-white in color; length 22 mm.; width 25 mm.; 

 depth 14 mm. : Florida reefs and the West Indies, in 100 

 to 200 fathoms; abundant. 



3. TEREBRATELLA D 'Orbigny. Shell ovoid or round ; 

 loop long and like Waldhelmia, but with its principal 

 stem twice attached: 9 species. 



T. transversa (Sowerby) (Fig. 440). Shell variable 

 in shape, usualty wider than long; length 30 mm.; 

 breadth 38 mm.; depth 20 mm.; color from light yellow 

 to dark purple: Monterey, California, northwards, in 15 

 to 20 fathoms, the commonest brachiopod on the coast. 

 T. spitzbergensis Davidson. Shell whitish-yellow and longer than 

 wide; valves equally convex, smooth, and strongly punctate; length 9 

 mm.; breadth 7 mm.; depth 3.5 mm.: circumpolar; 

 south to Gulf of St. Lawrence, in 40 to 400 fathoms. 

 4. LAQUEUS Dall. Shell broadly ovoid; loop 

 long like Terebratella, but with the reflected portion 

 attached by a connecting branch on each side to the 

 principal stem: 3 species. 



L. californicus (Koch) (Fig. 441). Shell 6 cm. 

 long, 5 cm. broad, and 25 mm. deep; bright yellowish or reddish-brown 

 in color : Santa Barbara County, California, and northwards, in 90 fathoms, 

 being smaller towards the north. 



Fig. 440 Tere- 

 bratella trans- 

 versa (Keep). 

 A, natural posi- 

 tion, with the 

 dorsal shell 

 uppermost ; B, 

 dorsal aspect. 



Fig. 441 



Laqueus californicus 

 (Keep). 



