KEPORT ON THE LAMELLIBRANCHIATA. 165 



prominent, well incurved and glossy at the apex. The interior of the valves is white, 

 faintly radiately substriated, minutely denticulated upon the margin, and exhibits a 

 slight ridge or angulation from the beaks to the lower hinder extremity. 



Length 4|- mm., height 4\, diameter 3|. 



Habitat. — Station 188, south of New Guinea, at a depth of 28 fathoms; green mud. 



The above dimensions do not probaljly indicate the maximum size attained by this 

 species, but the peculiarity of the sculpture is such as to warrant the description of these 

 possibly young shells. The position of the tubercles in the grooves, and not upon the 

 intervening costellae, is most unusual. 



Family Verticordiid^. 



Verticordia, Searles Wood. 



This genus and Pecchiolia of Meneghini closely resemble each other in general 

 outward appearance and as regards the hinge-characters, and possibly may be identical 

 from a generic point of view, although this has still to be clearly demonstrated. If they be 

 the same, it then becomes questionable whether the more recent name Pecchiolia should 

 be adopted, as has been done by Jeffreys and others, on the ground that Verticordia was 

 preoccupied in botany. Considering the difference of opinion upon this point, the 

 uncertainty of their identity, and that the name Verticordia has been employed by such 

 excellent authorities as Fischer, Dall, and Stoliczka, I prefer to adopt the views of these 

 writers rather than follow that expressed by Dr. Gwyn Jeffreys in this matter. I 

 should here remark that the last named author not only considers the two forms in 

 question identical, but unites with them Lyonsiella of Sars, a genus, as already pointed 

 out by Heilprin,^ which is very different both as regards the shell and animal. Our 

 knowledge of the soft parts of Verticordia is very incomplete at present ; but the 

 observations of A. Adams ^ show that they differ from those of Lyonsiella in more than 

 one particular. 



The following species I regard as true Verticordice : — (l) Verticordia cardiiformis, 

 J. Sowerby ; (2) Trigonulina ornata, d'Orbigny ; (3) Verticordia novemcostata, Adams 

 and Reeve; (4) Hippagus acriticostatus, Fhi\ii)]}i ; (5) Verticordia deshayesiana, Yischev; 

 (6) Verticordia japonica, A. Adams ; (7) Verticordia multicostata, A. Adams ; (8) 

 Verticordia granulata, Seguenza ; (9) Verticordia coelata, Verrill ; (10) Verticordia 

 australiensis,^VQ\t\i; (11) Verticordia Jischeriana,'Da}t\.; (12) Verticordia elegantissima, 

 Dall; (13) Verticordia arenosa, Smith; (14) Verticordia^ quadrata, Smith; (15) 



1 Proc. Acad. Nat. Sci. Philad., 1881, p. 423. 2 ^,„i. and Mag. Nat. Hist., 1862, ser. 3, vol. ix. p. 224. 



