RANDOM NOTES ON NATURAL HISTORY. 



The Shell - Bearing Mollusca of Rhode 

 Island. 



[BV HORACE F. CARPENTER.] 



Chapter IX. 

 Genus Columbella, Lam. 



Shell strombiform, fu.siform, or obovate ; 

 smooth, or longitudinally or transversely 

 ribbed, or striate ; inner lip excavated in 

 the middle, crenulated or denticulated in 

 front; outer lip usually inflected, thickened 

 within, and crenulated in the middle. 



This genus is subdivided into eleven sub- 

 genera, two of which are represented in 

 Rhode Island. 



Sub-Genus Mitrella, Risso. 



Shell mitriform, smooth or longitudinallj- 

 plicate ; spire elevated, sharp ; body-whorl 

 suddenly narrowed into a beak or short 

 canal in front. This sub-genus includes 

 Ast3 ris and Amycla (in part) of H. & A. 

 Adams. 



Sub-Genus Anachis, H. & A. Adams. 



Shell oval-fusiform, longitudinally ribbed, 

 spire elevated ; body-whorl not narrowed in 

 front; aperture narrow ; columella straight; 

 outer lip nearlj' straight, crenulated within. 



13. Columbella (Mitrella) lunata. 



Say. 

 Syns. : 



Nassa lunata, Say. 1826. 



Buccinum lunatum, Adams. Gould. 



Buccinum Wheatley's, DeKay. 



Coluuibella Gouldiana, Agassiz, Mss. 

 Stim. 



Astyris lunata, Dall. 



Distr., Massachusetts to Florida. Very 

 abundant in Vineyard Sound, from low 

 water to ten fathoms. Their station is on 

 seaweed, and the best method of obtaining 

 them alive is to pass a dredge (having a 

 coarse cloth on each side as a protection to 

 the iron work) through a belt of seaweed, 

 as the boat passes through it; on pulling in 

 the dredge, the cloth will !)e found covered 

 with these shells, which may be scraped off 

 with a knile, or removed to a small bottle 

 with a tooth-pick, which is my favorite 

 method of collectinu- sinall shells. These 



shells are small, ovate-conic; whorls six, 

 surface smooth, color reddish-brown, with 

 from one to three series of sub-lunate spots 

 on the body- whorl, va lying from white to 

 dark yellow in color ; on the lower part of 

 the base are several revolving lines; aper- 

 ture oval, narrow, ending in a very short 

 canal ; outer lip simple, dentate within ;. 

 inner lip smooth and brown. Length ^ 

 inch, breadth ^\. 



14. Columbella (Mitrella) uissimilis, 

 Stimpson. 



Shell veiy minute, j^-^-^ inch in lengthy 

 j^-^ inch in breadth ; whorls five, flattened ; 

 aperture a little less than half the length of 

 the shell ; color fuscous, with three white 

 zones ; surface longitudinally striate, and 

 destitute of revolving lines on the rostrum. 

 It inhabits the Laminarian zone, and has- 

 been found at Eastport and Grand Manan 

 by Stimpson, and in Vineyard Sound by 

 Verrill. It was first discovered at Ston- 

 ington by Linsley, in 1845, and named b}' 

 him Buccinum zonalis, without description. 

 I have never seen this species. It has not 

 yet been observed in Rhode Island, prob- 

 ably on account of its minute size. 



15. Columbella (Anachis) avara. Say. 



Shell elongated-ovate, solid, of a light 

 straw color, blotched with various shades of 

 reddish-brown, surface covered with equi- 

 distant revolving lines, reticulated by fifteen 

 smooth, obtuse ribs, running from the apex, 

 and terminating at the centre of the body- 

 whorl, leaving the lower portion marked 

 only b}' the revolving lines ; whorls six, 

 forming a pointed spire ; aperture narrow,. 

 about one-third the length of the shell ; 

 outer lip simple, thickened externally and 

 toothed internally; inner lip callused and 

 also dentate in mature specimens. Length 

 I inch, breadth |. 



This shell was described by Sav, in .June, 

 1822, Jour. Acad. Sri., Pldl.^Vol. 2. p. 

 281, as Columbella arara. He says, '• It 

 inhabits the coasts of the Southern States, 

 and occurs as far north as Maryland." It 

 is found at Martha's Vineyard, Nantucket, 

 and New Bedford, but not to the north of 

 Cape Cod. It inhabits deep water at New- 

 port. I have never seen even dead shells 

 above Bristol Ferry, l)ut have found them 

 abundantlj' on the island of Rhode Island. 



