APPENDIX 11. 



Since receiving the specimens described in the preceding Appendix, a few others 

 have been forwarded to me for examination. They consist of a Malletia, a Leda, a 

 Glomus, one Limopsis, two species of Area, and a Spondylus. They are of special 

 interest in coming frorn Stations from which Lamellibranchs have not previously been 

 reported, and all, excepting the Limopsis and the Arcce, are new and very interesting 

 species. 



Malletia dunkeri, n. sp. 



Testa parva, intequilateralis, uitidissima, iridescens, semipellucida, tenuissima, vix 

 concentrice striata, oblonga, antice angustata, acute rotundata, postice latior, sub- 

 quadrate arcuata. Margo dorsi anticus brevis, declivis, vix arcuatus, posticus longior, 

 rectiusculus, horizontalis ; margo inferior late curvatus. Umbones parvi, albidi, aliquanto 

 obtusi, circa in ^ longitudinis coUocati. Dentes cardinis ad sedecim in utraque valva, 

 hand acuti. Ligameutum externum augustum, lineare. 



This species is considerably inequilateral, excessively thin, semitransparent, highly 

 glossy, iridescent, and exhibits but very faint lines of growth. It is longer than high, 

 narrower and more sharply rounded in front than behind. The front 

 portion of the dorsal margin is short, very sloping, and a little 

 excurved. The posterior side is much longer, horizontal, and also ^^ 

 only very little arcuate. The ventral outline is widely curved, and ifaiutia^i^iTn sp 

 ascends obliquely behind rather further than in front, so that the 

 posterior extremity is higher up than the anterior. The beaks are rather obtuse, very 

 little prominent, opaque white, and situated at less than a third the length of the shell 

 from the anterior end. The hinge consists of about sixteen squarish-topped teeth in each 

 valve, of which about ten are behind the umbones and the rest in front, and, owing to 

 the thinness and transparency of the shell, are clearly visible when the valves are closed. 

 The ligament is very slender, and, commencing between the beaks, extends a short 

 distance behind them. 



Length 5 mm., height 3i, diameter 2;^. 



