452 PROCEEDINGS OF THE ACADEMY OF [1881. 



authenticated specimen of A. hians) tliat the two species are in 

 fact identical, despite the supposed distinctions pointed out by 

 Tuouiey and Holmes. 



A. soalaris Conr. (Scapharca) N. Car. ; Va. 



Proc. A. N. S., i, p. 324 ; Mioc. Foss., p. 59. 



A. subrostata Cinr. (Scapharcn), Md. 



Proc. A. N. S., i, p. 30. Mioc. Foss., p. 58. 

 A. tenuicardo Conr. Am. Journ. of Conchology, v, p. 39. 



A. subsinuata Conr. (Scapbarca). N. Car. 



Mioc. Foss., p. 62. 



A. transversa Say (Scapbarca). Va.; N. Car 



J. A, N. S., ii, p. 269. Conrad, Foss. Shells Tert. Form., p. 15; 

 Emmons, Geol. of North Carolina, 1858, p. 285. 



I have but little doubt that the species here described is one of 

 tlic various forms of A. plicatura. 



A iriquetra Conr. (Scapbarca), Md. 



Proc. A. N. S., i, p. 305. Mioc. Foss., p. 59. 

 = A. staminea? Say, "American Conchology," p. 36, fig. 2. (In Say's 



description the anterior extremity of the shell is described as the 



posterior, and vice versa). 



Somewhat resembles the recent A. rhombea (Born). 



Pliocene. 



A. caelata Conr. (Barbatia). S. Car. 



Mioc. Foss., p. 61. Tuomey and Holmes, Plioc. Foss., p. 36. 



A. centenaria Say (Striarca). S. Car. 



J. A. N. S., iv, p. 138. Tuomey and Holmes, Plioc. Foss., p. 37. 



.A. incile Say (Anadara). S. Car. 



J. A.N. S., iv, p. 139. Tuomey and Holmes, Plioc. Foss., p. 35. 



A. incongrua Say (Scapbarca). S. Car. 



J. A.N. S., ii, p. 268. Tuomey and Holmes, Plioc. Foss., p. 45. 



A. pexata S 'y ( Argina). S. Car. 



J. A. N. S., ii, p. 268. Tuomey and Holmes, Plioc. Foss., p. 46. 



A. soalaris Conr. (Scapharca). S. Car. 



Proc. A. N. S., i, p. 324. Tuomey and Holmes, Plioc. Foss., p. 43. 



A. lienosa Say (Scapbarca). S. Car. 



American Conchology, PI. 36, fig. 1. Tuomey and Holmes, Plioc. 

 Foss., p. 40. 



A. plicatura Conr. (Scapharca). S. Car. 



Mioc. Foss., p. 61. 

 A. improcera (young) Conr. ; Tuomey and Holmes, Plioc. Foss., p. 41. 



