398 TELLINID^S. 



P. Ferrbensis was probably the Tellina trifasciata of 

 Linne, as Mtiller believed. According to Loven it is 

 the T. incarnata of the f Fauna Suecica/ but not of the 

 1 SystemaNaturse.' It is strange that Linne referred to 

 the same figure in Lister's f Historise animalium Anglise 

 tractatus" (App. t. 1. f. 8) both for T. incarnata and T. 

 trifasciata. That figure undoubtedly represents the pre- 

 sent species. It is the T. angulata of Born (but not of 

 Linne) , T. incarnata of Pennant, T. racliata of Da Costa 

 (but not of Linne), T.fervensis and T. Bornii of Gmelin, 

 T. truncata of Spengler (but not of Linne), and (in its 

 immature state) the T. muricata of Renier; S. Wood 

 has noticed four other names given by palaeontologists. 



4. P. vesperti'na*, Chemnitz. 



Lux vespertina, Chemn. Conch.-Cab. vi. p. 72, t. 7. f. 59, 60. P. vesper- 

 Una, F. & H. i. p. 271, pi. xix. f. 1, 2. 



Body suboval, elongated, yellowish-white : mantle finely 

 fringed : tabes long, and apparently rather wider than in P. 

 Ferroensis; the branchial has six points at its orifice; the 

 other is curved, and its terminal margin is irregular: gills 

 hanging obliquely from the dorsal range, of a brown colour, 

 rather coarsely pectinated; the upper pair are shorter and 

 smaller than the lower: palps triangular, elongated and 

 pointed, of a lighter colour than the gills, smooth on their outer 

 surfaces and distinctly pectinated within ; they are of equal 

 length, and each pair is connected with the other by a mem- 

 brane surrounding the mouth : foot very large, broad, and 

 rather thick. 



Shell of a form between oval and oblong, or partly rhom- 

 boidal owing to the angularity of the posterior side, compressed, 

 rather solid, opaque, more or less glossy when not covered by 

 the epidermis : sculpture, numerous irregular and usually ob- 

 scure concentric ridges, which are more observable in large 

 specimens near the margins ; the parallel and occasional lines 



* Name derived from the similarity of the coloured streaks on the 

 shell to the rays of the setting sun. 



