MARINE MOLLUSCA OF THE UNITED STATES. 59 



nearly closed and consisting only of an arcuated, linear, vertical, 

 aperture. 



Length about 6 mill. 



Buzzard's Ba}'. Dredged in three to eight fathoms. (Stimpson.) 



Massachusetts to N. Carolina. 



Genus LUNATIA, Gray. 

 Zool. Proc. 1847. 



1, L, HERDS, Say. Fig. 96, 97 (triseriata), 98 (Nidus), 99 (Ani- 



mal). 

 (Naiica.) Jonrn. Philada. Acad., ii. 248. 1823. 

 iV. catenoides, S. Wood, 1848 (teste Jeffreys.) 

 Vat: N. triseriata Say. Journ. Pliila. Acad., v. 209. 



Shell large, thick, globular-ovate; whorls five, convex; spire 

 considerably elevated. Aperture oval ; the callus reflected over a 

 small portion of the large, patulous, and coarsely wrinkled um- 

 bilicus. Epidermis thin and yellowish; beneath this, ashen gray. 

 Aperture dark reddish-brown occasionally tinged with yellowish. 



Occasionally grows to the length of five inches. The young 

 shell is sometimes marked by three revolving series of parallel 

 oblong brown spots, twelve or fourteen in each row (N. triseriata). 

 These markings are lost on the subsequent whorls. 



The nidus is composed of sand agglutinated into a bowl-shaped 

 mass, open at the top. The eggs are attached to the interior sur- 

 face. 



This maybe the N. ampullar ia of Lamarck, as surmised b^'- some 

 of our conchologists, but the description does not sufficiently 

 characterize it, 



Ifew England, southward to New Jersey. 



2. L. Grcenlandtca, Moller. Fig. 100, 



iNatica.) Faun. Groenl., 7. 1842. 

 Nalica piisilla, Gould (not Say), Invert. Mass., edit. i. 237, f 166. 1841. 



Shell suboval, smooth, glossjr or with faint incremental and re- 

 volving lines; whorls four, regularly rounded ; spire moderately 

 elevated, obtuse ; suture distinct and deep ; lip sharp, acute ; callus 

 pressed laterally into the umbilicus, leaving a narrow curved linear 

 opening. Epidermis ash-colored, beneath bluish-white. 

 Length 12.5, diam. 11 mill. 



Massachusetts northwards. 



