676 



This species presents a medium between A. variegata and A. 

 exoleta in general appearance, and in the character of the ribs 

 and markings. The ribs are much more close and flat than in 

 A. variegata. 



Philippines. Cuming. 



Genus LUCINOPSIS, Forbes 8f Hartley. 



Lucinopsis undata (pi. cxliv. f. 88, 89). Venus undata, 

 Pennant, Brit. Zool. vol. iv. pi. 55. f. 51. Venus sinuosa, Id. 

 Lucina undata, Tnrton. Venus iucompta, Philippi. Cythersea 

 undata, Macgil. Artemis undata, Alder. 



L. testa tenui, inflata, pallide Mva, subquadratim rotundata, 

 irregulariter et leviter substriatil; margine dorsali subelevato; 

 margine postico subsinuato ; cardine postice subcomplanato, den- 

 tibus in valva sinistra tribus ccntralibus, quarum medio dupli- 

 cate, in valva dextra duobus ; ligamento magno, interne compla- 

 nato ; impressione pallii sinu magno rotundato. 



It seems doubtful whether the characters named by the pro- 

 posers of this genus are sufficient to distinguish it from the Ar- 

 temides. The teeth slightly differ, and the sinus in the muscular 

 impression is less angular. 



A well-known species, found in various parts of the British 

 coasts. 



LIST OF FIGURES IN PLATES CXL. TO CXLIV. 



{The Figure after each name is the number of the Species) 



Fig 





rig. 







Plate CXL. 



6. 



A. simplex, 8, Hani. 



1. 



A. concentrica, 1, Gmel. 



7. 



— incisa, 5, Reeve. 



2. 



— ponderosa, 3, Gray. 



8. 



— Patagonica, 6, PJi. 



3. 



— distans, 2, Sowb. ? 



9. 



— discus, 10, Reeve. 



4. 



— concirma, 9, Sowb. 



10. 



— - plana, 11, Reeve. 



5. 



— Dimkcri, 7, Ph. 



11. 



— nitens, 11, Reeve. 



