06 THE VOYAGE OF II. M.S. CHALLENOER. 



assigned to it, uamel)" Senegal, I reganl merely as one of tlie numerous errors of this 

 description occurring in the collection of Mr. Cuming. 



Bubfamil}^ Tkllinin^. 



Tellina, Linne. 



Tellina (Macoma) consociata, n. sp. (PI. IV. figs. 4-4?^). 



Testa paulo insequilateralis, ovato-trigonalis, alba, epidermide caduca lutescenti induta, 

 postice parum hians, dextrorsum subflexuosa, valva dextra quam sinistra aliquanto 

 planiore, parte antica subelongata, ad finem medioeiiter acute rotundata, postica multo 

 breviore, cuneiformi, ad extremitatem oblique truucata ; valvse tenues, subnitentes, incre- 

 menti lineis tenuibus striatfe. Margo dorsi anticus declivis, subrectilinearis, elougatus, 

 posticus magis obliquus, rectus, brevior, margo ventralis late arcuatus, antice regulariter 

 adscendens, postice vix flexuosus. Dentes cardinales valvpe dexbraj duo, posteriori bifido, 

 in sinistra unicus pariter bifidus. Pallii sinus maguus, spatium subquadrangulare in- 

 cludens. Pagina interna alba, radiatim suljstriata. 



This shell is moderately thin, somewhat inequilateral and inequi\'alve, the right being 

 slightly less convex than the left. It is longer than high, triangularh' ovate, sharply 

 rounded in front, wedge-shaped, and shortly truncated behind, very slightly gaping at the 

 posterior end, which is bent a little to the right. It is of a pure white colour, more or 

 lass concealed by a clay-coloured caducous epidermis which is a little reflexed within the 

 margin of the valves. The sculpture consists of fine concentric lines of growth and traces 

 of radiating substrise. The umbones are small, acute, and located somewhat behind the 

 central point. The front dorsal margin is long, onl}- slightly oblique, almost straight or 

 very feebly excurved, the posterior lieing rather shorter, rectilinear, and very sloping. 

 The ventral outline is gently curved, a little more ascendant in front than l)eliind, where 

 there is only the faintest indication of a sinus. Both valves are shallowly grooved down 

 the posterior side, the left rather more distinctly than the right. The hinge consists 

 of two cardinal teeth in the right valve and one in the left, the posterior in the former 

 and that in the latter being cleft at the summit. The interior of the valves is white, and 

 marked with faint radiating substrise. The pallial sinus is large, and extends considerably 

 beyond the centre, the circumscribing line forming a somewhat quadrangular figure. 



Length 22 mm., height 151, diameter 8. 



Habitat. — South of Amboina, at a depth of 15 to 25 fathoms. 



This species closely resembles the shell figured by Hanley (Thesaurus, fig. 13) as the 

 Tellina umbonella of Lamarck. The locality, " Port Lincoln," which he assigns to it is 

 probably taken from a specimen in the British Museum said to have come from that place. 

 In the Proceedings of the Zoological Society, 1871, p. 727, I quoted this species from 



