56 THIC NAUTILUS, 



new admiration is evoked, and what is better fitted to call it forth 

 than a careful study of the beautiful objects of nature. Moreover, 

 observation is quickened, interest aroused, and knowledge is increased. 

 The danger which lies in the spread of popular science is not found 

 in the contemplation of real facts and real objects, even if they are 

 studied but slightly; it must be sought, rather, in the substitution of 

 fancies for facts, and a superficial reading or hearing about things 

 instead of an examination of the things themselves. 



Among other good results of the session was the formation of a 

 club of subscribers for The Nautilus, with the prospect of addi- 

 tional names in the future, as its merits become known. 



THE SHELL-BEARING MOLLUSCA OF RHODE ISLAND. 



BY HORACE F. CARPENTER. 



FAMILY LITCINIDvE. 



This family contains about one hundred and fifty species, dis- 

 tributed chiefly in the tropical and temperate seas, on muddy and 

 sandy bottom from low water to the deepest water inhabited by the 

 mollusca. Several of the genera are entirely fossil. 



Genus Luc'ina, Brug., 1792. 



There are two hundred and fifty fossil species and one hundred 

 living. Distribution universal. 



179. — Lucina {Cyclas) denUda., Wood, 1817. 



Syns. : 



Lucina divaricata, Gld. Lam. non Linne. L. strigiUa, Stimp., 

 L. americana, C. B. Adams, L. chemnitzi, Phil., L. lamarckii, Dunker, 

 L. eburnea, Reeve, L. Pilnla, C. B. Adams, L. orncda, Reeve, 

 L. quadrisulcata, D'Orb., Pectimculus parvus, Lister, Tellina divari- 

 cata, Gmel. Chemn. Dillw. Turton, Cydas dentata, Dall, Tryon, 

 Verrill, etc. 



Shell white, thin, orbicular, convex, sub-equipartite ; beaks cen- 

 tral, elevated, inclined forward ; surface glossy and sculptured in a 

 very peculiar manner, with grooves bent obliquely downwards from 

 a line drawn, not through the center, but from a point at the 

 anterior third ; they extend to the margins and crenulate the 



