PECTEN. 167 



It is quite robust, and its surface is marked by about 

 twenty strong ribs, which are separated by deep and 

 equal furrows. Whitish, more or less mottled and 

 striped with reddish brown. Large specimens are 

 three inches across. 



Pecten latiauritas, Conr., lat-i-au-ri'-tas. The ribs 

 of this shell are about twelve in number, plain and 

 distinct. The ears, or flattened parts of the shell 

 upon each side of the umbo, are broad, suggesting 

 its specific name, which means broad-eared. You will 

 notice that one of the ears of each Pecten is notched, 

 allowing a little space for the finger-like foot to pass 

 through without opening the shell. This foot spins a 

 byssus of horny threads, and attaches them to some 

 support, thus casting anchor when the animal wishes 

 to remain fixed. The color of this southern shell is 

 white and brown, and it is one inch in diameter. 



Fig. 140 introduces us to another of the Comb- 

 shells, Pecten monotimeris, Cour. , mon-o-tim'-e-ris. 

 Shell very thin and delicate, ribs 

 rounded and rather faint, ears unequal, 

 color inclining to yellow or brown, 

 but variously mottled with white, like 

 the feathers of a speckled hen. Out- 

 line nearly circular; usually less than 

 Fig. 140. an inch in diameter. 



Pecten hastatus, Sby., has-ta'-tus, Fig. 141. This 

 exquisitely beautiful species is essentially a northern, 

 deep-water inhabitant, though it is occasionally found 

 quite far down the coast. The shell is thin, the ears 

 very unequal, and the edges of the principal ribs are 

 cut into many short and slender teeth. The valves 

 differ from each other, both in sculpturing and in 

 color, the lower one being nearly white, while the 



