MOLLUSCS. 



M 



srejitics, tliiit ll 



lese WL'iv 



merely shells 



structure, a condition characteristic of thi' young of tlie higher forms. The foot is 



small, and frequently sj)ins a hyssus, by which the animal attaches itself. 

 The tyjiieal genus of the 



family is Pecten, in which the 



regular shell is usually ribbed, 



the lines radiating from the 



umbo. The anterior ears of 



the shell are the larger. In 



older times sijecies of this 



genus were known as "•]ii]- 



griras' shells," from the fact 



th.at for some unknown reason 



the pilgrims of the middle ages 



were wont to ornament thi ii 



clothing with these shells. S. ■ 



prevalent was the practice, 



that when, in the early days of 



science, it was adduced as a 



])roof of the biblical record of 



the flood that fossil shells were 



found in the Alps; the reply was made by 



dropped by pilgrims returning from Palestine. 



The common scalloi' of the southern shores of New England is known in scientitic 



terminology as Pecten irradkms. It li\es 

 HI sh illow places, among the eel-grass, and 

 >~\Mms away at the slightest alarm. This 

 s\\ nnnung, which is somewhat rare among 

 bn ih e molluscs, is effected by rapidly ojien- 

 111 o and closing the valves of the shell, the 

 , icvult being a sub-aquatic flight in a back- 

 . \\ u<l direction. In color this species varies 

 I- ( ( 1 iiisiderably, but the flat valve is always 

 / hghtei than the other, being often white. 

 <i The other valve may be reddish, orange, 

 ]iuiplish, oi- mottled with two of these colors. 

 Tilt eves, upon the edge of the mantle, are 

 ^ihti or bluish, and are thirty or more in 

 iiuinbc I. This is the scallop of the markets, 

 ^nd IS highly jirized by some, though its 

 sweetish taste makes it unpleasant to others, 



while some find it actually unliealthy, and productive of nausea. Only the adductor 



muscle is eaten. 



North of Cape Cod this s]>ecies is rej^laced by two larger ones, P. islandiries and 

 P. tenuicostatus, neither of which are of much economic importance. In Europe the 

 scallop (P. maxim as) and the quin {P. opcradaris) are extensively eaten. Other 

 species, nearly two hundred in number, are found in all the seas of the world. 



In Lima the shell is obliquely oval, and gapes anteriorly. The hinge is straight, 

 toothless, and the ears are small. The border of the mantle is fringed with long cirri, 



