V 



NATURAL SCIENCES OF PHILADELPHIA. 75 



ECHINIANTHUS, Breynius. 

 E. Mortonis, (Pyrgorhyncus) Mich. Rev. et Mag. de Zool., 1850, 2. Desor., 



Synop. des Echin. 295. Miss. 



CASSIDULUS, Lam. 



C. amygdala? Desor., Synop. des Ecbin. lxv. 



C. Conradi, (Catopygus) Couper, Journ. Acad. Nat. Sci., iv. 2d series, 39, 1, 



9. Georgia. 

 C. Lyelli, (Nuclaolites) Con., Journ. Acad. Nat. Sci., ii. 2d series, 40, 1, 14. 



Georgia. 



C. patelliformis, (Catopygus) Bouve, Bost. Soc. Nat. Hist., iv. 2. Georgia. 



Cassidulus patelli/orjiiis, Desor., Synop. des Echin. 290. 



HEMIASTER, Lam. 

 H. Conradi, Bouve", Bost., Soc. Nat. Hist., v., 2d series, 3. Georgia. Desor., 

 Synop. des Ecbin. 373. 



DISCOIDEA, Lam. 



D. Haldemani, C, Journ. Acad. Nat. Sci., iv., 2d series, 40, 1, 12. Georgia. 



ECHINOCARDIUM, Gray. 



E. orthonotus, (spatangus) C, Proceed. A. N. S. 1, 327. Virg. 



Amphidetus Virqinianus, Forbes, Quart. Journ. Geol. Soc, i. 425. 

 Echinocardium Virginianum, Desor., Synop. des Ecbin. 408. 



Cirripedia. 

 BALANUS, Lin. 

 B. bumilis, C, Amer. Journ. Sci., ii., 2d series, 400, f. 4, Florida. 

 B. peregrinus, Morton, Organic Rem. of Cretac. Group, 72. S. C. 



Descriptions of new species of ECHINID2E. 

 BY T. A. CONRAD. 



SISMONDIA, Desor. 



S. alta. Suborbicular ; margin thin, disk gradually rising towards the 

 centre and concave in outline ; central portion elevated and obliquely flattened 

 at the summit ; ambulacra lanceolate, nearly closed ; anus subquadrangular, 

 thin, position nearer the mouth than the posterior end ; margin thin, un- 

 dulated. 



Scutella, Emmons, Geol. of North Carolina. 



S. marginalis. Subovate or suborbicular, depressed ; ambulacra lanceo- 

 late ; central prominence rounded, margin thicker than the submarginal area 

 of the disk ; truncated posteriorly, emarginated ; anus subquadrangular, 

 minute, situated near the margin, which is thickened beneath. Diameter 

 inch. Height ' inch, S. C. 



S. plana. Discoid, subovate, very thin, margin slightly thickened, disc 

 convex depressed, summit anterior to the middle ; ambulacra broadly lanceo- 

 late, nearly closed ; anus distant from the margin, but nearer to it than to the 

 mouth. Longitudinal diameter ii of an inch ; transverse diameter JL inch. 



s.c. lb lS 



Descriptions of three new species of Exotic UNIONES. 

 BY ISAAC LEA. 



Unio Wrightii. Testa, plicata, lata,, ad umbones inflata, valde inaequilate- 

 rali, postice acuto-angulata, antice rotundata, ; valvulis crassiusculis, antice 

 craasioribus ; natibus subprominentibus et crebre plicatis ; epidermide tene- 



1865.] 



