CONCHIFERA. 



411 



Pecten, 0. F. MuUer. Scallop. 



Etymoloyy, peden, a comb. 



Type, P. maximus (Janira, Scliuin.) 



Synonyms, Argus, Poll. Discites, Schl. Amusinm, Mulilfeldt. 



Shell sub-orbicular, regular, resting on the right valve, 

 usually ornamented mth. radiating ribs ; beaks apj)roxiniate, 

 eared ; anterior ears most prominent ; posterior side a little 

 oblique ; right valve most convex, with a notch below the front 

 ear ; hinge-margins straight, united by a narrow ligament ; 

 cartilage internal, in a central i)it ; adductor impression double, 

 obscure ; pedal impression only in the left valve, or obsolete 

 (Fig. 210). 



Animal vdih the mantle quite open, its margins double, the 

 inner pendent like a curtain 



{m) finely fringed ; at its 

 base a row of conspicuous 

 round black eyes {ocelli) sur- 

 rounded by tentacular fila- 

 ments ; gills {b?') exceed- 

 ingly delicate, crescent- 

 shaped, quite disconnected 

 posteriorly, having separate 

 excurrent canals ; lips folia- 

 ceous ; palpi truncated, plain outside, striated within ; foot 

 finger-like, grooved, byssiferous in the young. 



The Scallop (P. maximus) and " quih " (P. ojjercularis) are 

 esteemed delicacies ; the latter covers extensive banks, especially 

 on the north and west of Ireland, in 15 to 25 fathoms water. 

 The scallop ranges from 3 — lOfathoms ; its body is bright orange, 

 or scarlet, the mantle fawn-colour, marbled with brown ; the 

 shell is used for "scalloping" oysters, formerly it was em- 

 ployed as a drinking-cup, and celebrated as such in Ossian's 

 "hall of shells." An allied species has received the name of 

 "St. James's shell" (P. Jacohoeus); it was worn by pilgrims 

 to the Holy Land, and became the badge of several orders of 

 knighthood, t 



Most of the Pedens spin a byssus when young, and some, 

 like P. varius, do so habitually ; P. niveus moors itself to the 

 fronds of the tangle [Laminaria). 



* The Pectens do not open so wide as here represented; tlieir " curtains " remain 

 in contact at one point on the posterior side, separating the branchial from the exhalent 

 cun-ents. 



t When the monks of the ninth century converted the fisherman of Gennesaret into 

 a Spanish wan-ior,l hey assigned him the scallop-shell for his "cognizance." (Moule's 

 •' Heralui-y of Fish.") 



T 2 



Fig. 216. Fecten varius. 



