26 Proceedings of the Biological Society of Washington. 



Palletes not consisting of a series of cone-in-cone structures . . . Teredo. 

 Pallettes paddle-shaped. 



Terminal portion of the blade cupped. 



Cup single Teredo. 



Cup not single. 



Cup rendered double by a median septum . . . Teredothyra. 

 Terminal portion of the blade not cupped. 



Terminal portion of the blade ending in a forked tip . . . Lyrodus. 

 Terminal portion of the blade not ending in a forked tip. 



Terminal portion ending in a calcified knob .... Teredops. 

 Pallettes not paddle-shaped. 

 Pallettes spoon shaped. 



Terminal portion of the blade cupped Neoteredo. 



Terminal portion of the blade not cupped Teredora. 



Bankia was proposed by Gray in 1840,' and Teredo bipalmidata Lamarck 

 was designated as type by him in 1847. ^ 



Neobankia new subgenus, type Bankia (Neobankia) zeteki new species. 



Bankiella new subgenus, type Bankia (Bankiella) mexicana new species. 



Nausitora was proposed by Wright in 1864^ type Nausitora dunlopei 

 Wright. 



Teredo was proposed by Linnaeus in 1758,* ty])e Teredo navalis Linnaeus. 



Teredothyra new subgenus, type Teredo (Teredothyra) dominicensis new 

 species. 



Lyrodus was proposed by Gould in 1870,^ type Lyrodus chlorotica Gould. 



Teredops new subgenus, type Teredo diegensis Bartsch. 



Neoteredo Bartsch, 1920,* type Teredo (Neoteredo) reynei Bartsch. 



Teredora new subgenus, type Teredo malleolus Turton. 



Bankia (Neobankia) zeteki, new species. 



Shell subglobular, white, the extreme anterior portion with the usual 

 sinus and reflected smooth callus at its external border, the main portion 

 bearing the dental ridges, which radiate from the anterior margin, where 

 they are closely crowded, backward to the junction with the posterior 

 median portion. Here they are separated by spaces about twice as wide 

 as the ridges. These ridges are finely denticulated at their free margin. 

 Seventy of these ridges are apparent, but at least twenty more appear to 

 have been eroded at the umbonal end. The anterior median area is rather 

 broad, and bears the closely crowded, strongly denticulated ridges, which 

 are separated by mere lines. These ridges terminate in a straight line pos- 

 teriorly. The middle portion of the median part is marked by the usual 

 groove that extends from the umbones to the basal margin, and this groove 



iSynop. Brit. Mus., p. 76. 



2Proc. Zool. Soc. London, p. 188. 



STrana. Linn. Soc, vol. 24, pp. 451-4. 



4Syst. Nat., 10th ed., p. 651. 



5Inv. Mass., p. 34. 



eProc. Biol. Soc. Washington, vol. 33, pp. 69-70. 



