REPORT ON THE LAMELLIBRANCHIATA. 163 



bumt-brown posteriorly, where some of the radiating costse are spotted with white. The 

 sculpture consists of about twenty-three ribs of different thickness, a few upon the 

 posterior side being more elevated and thicker than the rest. Four or five others 

 situated on the same side, but above those referred to, arc ornamented with strong white 

 scales. The interstices between the costse exhibit rather well-marked lines of growth, 

 which cross the ribs upon the anterior portion of the valves, thus producing a slightly 

 nodose appearance. The umbones are small, but very slightly raised above the hinge- 

 line, and located a long way in advance of the middle. The hinge is composed of a 

 single prominent cardinal tooth in the left valve, which fits in between two denticular 

 prominences in the right. The anterior lateral teeth are much approximated to the 

 cardinals, the posterior being very remote. The interior of the valves is coloured like the 

 exterior, deeply grooved and strongly dentate at the margin. 



Cardium (Lcevicardium) norvegicum, Spengler, var. 



Cardium norvegicum, Spengler, Forbes and Hanley, Brit. Moll., vol. ii. p. 35, pL xxxi. 



figs. 1, 2. 

 Cardium norvegicum, Rtimer, Conch. -Cab., ed. 2, p. 83, pi. xiii. figs. 3-6. 

 Cardium 7wrvegieum, Jeffreys, Brit. Couch., vol. ii. p. 294, vol. v. pi. xxxv. fig. 7. 



Habitat.- — St. Vincent, Cape Verde Islands, in 7 to 20 fathoms. 



The few shells from this locality are scarcely so oblique and pointed behind as more 

 northern specimens, the epidermis is thinner, and the valves are rather more vividly 

 spotted with a pinkish-brown tint. The species has not previously, I believe, been 

 found so far south. The West Indian species, Cardium glabratum, Romer ( = Cardium 

 loevigatum, Reeve, non Linn.), might almost be considered a variety. 



Cardium (Fraginn) medium, Linne. 



Cardium medium, Linn^, Syst. Nat., ed. 12, p. 1122. 



Cardium medium, Wood, Index Test, pi. v. fig. 5. 



Cardium medium.. Reeve, Conch. Icon., vol. ii. fig. 30. 



Cardium (Fragum) medium, Romer, Conch.-Cab., ed. 2, p. 102, pL iv. figs. 5-7. 



Habitat. — Station 113a, off Fernando Noronha Island, north-east of Brazil, in 

 25 fathoms ; volcanic sand and gravel. 



This is a well-known West Indian species, and is closely represented on the west side 

 of America by Cardium biangidatum and Cardium planicostatum. 



