WORMS, TESTACEA. 59: Caidium. a5 
Chemn. conch. 6, tab. 16, fig. 162—164. 
. Schret. Einl.in conch, 2, tab. 7, fig. 11. 
Nn: conch. 6: tab. 16, fig, 165? 
Inhabits European and American feas: refembles C. hemicardium. 
Shell marked with chefnut or brown ípots; ribs numerous, the 
intermediate grooves fmooth: valves on one fide a little trun- 
cate, but prominent in the middle: Z/zge with a fingle pri- 
mary tooth. 
# aculectum Shell fomewhat heart-fhaped ; the ribs high and grooved 
* Echina- 
fup. 
down the middle, and befet with large hollowed fpines 
. fiear the cirbum ference! 
Disbdta! s Britifb Shells, 1. tab. 6. 
Pennant Brit. Zevl.Yv. tab; 50. fi 37. 
Lifter conch. tab. 320 Barbut, tab. 3, fig. 10. 
Argenville conch. tab. 23; B. ^ Gualt. teft. tab. 72. A. 
Bonan. recr. 2. fig. 96,97. Muf. Kirch. 2. fte 955 97, 98. 
Seba Muf. 3. tab. 86. rig. 4. 
Murr. fund. tefiac. tab. 2, fig. 9 
Chemn. conch. 6. tab. 15, f: 155—157. 
2. Seba Muf. 3. tab. 86, fig. 5. 
3. Seba Muf. 3. tab. 86, fig. 8. 
4. Bora Muf. Cerf. Vind. teft. tab. 2, f. §. 
5. Benan. Muf. Kirch: 2. fig. 94. 
Inhabits European and Mediterranean feas; refembles C. echina- 
tum, but is longer, more consex and a little truncate on one 
fide, bat elevated towards the margin, with 2 ribs: yellowifh- 
brown with fometimes darker bands: Ainge with 2 teeth in 
each valve, lateral ones 2 in one valve iudi in the other. 
Shell lightly heart-fhaped; with carinate fpinous ribs. 
Penn. Brit. Zool, iv.p. go, v. 38. 
Lifier conch. tab. 324. An. Ang. tab. 5, fig. 53- 
Mull. Zool. Dan. 1. tab. 135; fig, 1, 2. f. 14, f. 1—4. 
Bonan. recr. 2. f- gos. Muf. Kirch. 2. f. 88. 
Gualt. Tefl. tab. 72. f. B... Clezn ofir. tab. 10, f. 40. 
Da cofta Brit. conch. tab. 14, f. 2. 
Seba Muf. 3. tab. 86. fig. 3 
Murr. tifiac. tab. 2. fig. 19. 
Left. Naturg. 1. tab, 1o, fig. 8. 
_ Chemn. conch, 6. tab, 15. fig. 158. 
2. Seba Muf. 3. tab. 86. sig. 13. 
3. Boman. recr. 2. fig. 72. Muf. Kirch. 2, f. 71... : 
lnhabits European Seas: white or tawny with white bands; 
ímaller than the laft and more rounded: the grooves deep, 
about 18, and wiinkled near the hinge: the prickles grow- 
ing larger from the middle towards the circumference, and 
none near the hinge, 
VOL. IV.—C c *Ciliare 
