BRACHIOPODA. 
15 
Terebratuladffi, Leach, MSS. 1818, Ann. Mag. N. H. xx. 273. 
Terebratulidae, Gray, Syn. B. M. 1840 ; 1842, 85, 92 ; Sow. Ann. 
N. H. 2nd ser. ii. 436, 1848 ; Wiegm. Arch. 1849, 98. 
M‘Coy, Curb. Foss. Ireland. 
King, Ann. 8f Mag. Nat. Hist, xviii. 26. 
Forbes ^ Hanley, Brit. Moll. ii. 343. 
D'Orb. Cours Pale'ont. 80. 1849. 
Terebratulacea, Menke, Syn. ed. 2. 95, 1830. 
Terebratulacea, part., Anton, Verz. Conch. 12. 21. 
Terebratulaceae, Menke, Syn. ed. 1. 56, 1828. 
Les Terebratules, F^russ. Tab. Syst. 1821. 
Rang, Man. Moll. 258. 
Terebratulinae, Agass. Nomen. 1847. 
Lingulae, part., Eichw. Zool. Spec. i. 275. 
Thecididae, part. (Megathyris), D’Orb. Ter. Cret. iv. 
Cyclothyridae, Phillips, Pal. Foss. Cornwall. 
Synopsis of Tribes and Genera. 
A. Loop attached to the hinge-plate. — Terebratulanina. 
1. Terebratula. 
2. Terebratulina. 
3. Waldheimia. 
B. Loop attached to the septum in the middle of the dorsal 
valve. — Magasina. 
4. Terebratella. 
5. Trigonosemus. 
6. Magas. 
7. Bouchardia. 
8. Megerlia. 
9. Morrisia. 
10. Kraussia. 
C. Loop attached to the surface of valve. — Argiopina. 
11. Argiope. 
Tribe 1. TEREBRATULANINA. 
Shell usually oval, valves convex, margins even or only slightly 
waved ; hinge-line curved ; beak of the larger valve perforated, 
the foramen quite at the apex ; deltidium of two pieces, often 
blended ; internal skeleton consisting of a slender shelly loop, 
not attached in the middle to the valve. 
