ASPIDOBRANCHIA. PATELLAD. 219 
Patella antiquata, Pult. Cat. Dorset. 51. t. xxi. f. 7, a.; 
Mont. Test. Brit. 485. t. xin. f. 9. 
Patella militaris, Turt. Conch. Dict. 140. 
Pileopsis mitrula, Lam. Hist. Nat. des Anim. sans Vert. vi. 18. 
Habitat in Danmoniz et Cornubie occidentalis, et in Caledonize 
Borealis mari profundo ; testis et lapidibus adherens. Alt. 
et long. 4 unc. 
Shell with its interior surface furnished with curved lamellee ; 
the epidermis roughish fuscous brown. Height and diameter 
half an inch. 
Inhabits the western coasts of Cornwall and Devon in deep 
water ; it adheres generally to dead shells, and sometimes, but 
rarely, on stones. 
ORDO VIII. CYCLOBRANCHIA. 
Branchie & foliis efformatze, inter pedes basin et pallium 
posite. Testa seepe exterior, seepe multipartita, nunquam 
operculata. 
FAMILY I. PATELLADA. 
Patella, Cuvier, Lamarck, De Montfort, &c. 
Festa integra, subconica, externa, dorsum tegens. 
Animal : caput et collum libera. Os rostriforme, retractile. 
Tentacula duo, depressa, ad basin externé dilatata, oculigera. 
Pallium \ateraliter dilatatum, intis testa marginem undique 
impositum, subtus branchias ferens. Pes ovalis. duus et 
oviductus ad dextram ad basin colli exeuntes. Cor anticum 
supra collum ad sinistram positum. 
Shell entire, subconic, external, covering the back. 
Animal: head and neck free. Mouth rostriform and retrac- 
tile. Tentacles two, depressed, dilated externally at their bases, 
bearing the eyes. Mantle dilated laterally, applied to every 
side of the shell, a little within its margin, bearing the branchize 
L2 
