3« 



LAMEIXIBRANCIIIATA. 



Zool. Soc. 1879, P-5 62 ' Smith, Challenger Report XIII, Lamellibranchiata, 1885, p. 317, PI. 24, 

 fig. 2; Fischer & Dautzenberg, Mem. Soc. Zool. de France, 10, 1897, p. 193; Locard, 

 Exped. scient. du Travailleur et dn Talisman, Moll. Test. II, 1898, p. 406. 



The shell slightly oblong-orbicnlar, the anterior margin more strongly curved outwards than 

 tlie posterior, which slopes fairly steeply down towards the ventral margin, compressed, the right 

 valve flatter than the left, somewhat translucent, glistening. The valves thin, the left almost smooth 

 or only with the margin provided with more distinct, concentric lines, the right valve on the other hand 

 with strong, rather dense, slightly elevated, concentric strife. Beaks small, little prominent, least on the right 

 valve. The ears well-developed, the posterior a little smaller than the anterior, with lamelhe-like lines 

 of growth; the anterior ear 011 the right valve with a small sinus at the base. The hinge-margin straight, 

 cartilage-pit small, triangular. The internal surface shining, with 10—15 elevated radiating ribs, 

 translucent on the outer side as milk-white stripes. Height 8.5 mm ., length 9 mm ., breadth 2.3 mm . 



It has been taken by the "Ingolf" Expedition at 

 St. 10. Denmark Strait 78S fm. 3.5 C 1 spec, and 10 valves. 



The above diagnosis, which is based 011 the specimens of the "Ingolf" Expedition, agrees on 

 the whole with that given by Jeffreys in Ann. Mag. Nat. Hist. (1876). A couple of small differences, 

 I believe, can be satisfactorily explained. For example, Jeffreys gives the number of radiating ribs 

 as 9, but the figure in Thomson's book shows 10; further, Edg. Smith found n on two shells pres- 

 erved in the British Museum and 14 usually on the "Challenger" specimens. Jeffreys says nothing 

 as to a byssal sinus in the anterior ear of the right valve, but that such is present can be seen in 

 the figure given by Edg. Smith. 



Distribution. Amtissium lucidum has a wide distribution within the northern and tropical 

 Atlantic 1 ): off the entrance to the Denmark Strait, 1450 fm. ("Valorous"); 49°27'N. L., i3°33'W.L., ca. 

 1100 fm. ("Thor"); N. and W. of Spain, 580—1100 fm. and N. of the Azores, 2240 fm. ("Travailleur", 

 "Talisman"); the Azores 1000 fm. and 725—1010 fm. ("Challenger", "Princesse Alice"); W. of Morocco 

 and W. of Soudan, 500—1385 fm. ("Travailleur", "Talisman") ; off Pernambuco in Brazil, 675 fm. ("Challenger"). 



Limidae. 



Lima loscombii Sowerby. 



Lima loscombii Sowerby, Genera of shells, 1820—24, Lima, fig. 4; Jeffreys, Brit. Couchol. 



II, 1863, p. 85, PI. 25, fig. 4. 



At the Faeroes, where it has not been known earlier, the species has been taken in recent 

 years at the following places: 



16 miles E. by S. of south point of Nolso ca. 80 fm. 1 valve. 



13 — W. by vS. of Muuken - 150 - 1 — 



6o°55'N.L., 8° 5 6'W.L 69- 1 — 



1 1 The form from the Southern Ocean referred by Jeffreys (1. e. 1S79) to A. lucidum as a variety (striata) has been separ- 

 ated by Edg. Smith (1. c, p. 316) as an independent species: A. meridionale. 



