Marshall. — F<unia of tht Hampden Beds. 233 



Sarepta^solenelloides u. sp. (Plate XV, figs. 4, 5, 6.) 



"^iiell of moderate size, 30 inni. higli, 15 mm. long, and 10 mm. thick. 

 Shape oval and slightly inequilateral, the anterior end being a little longer 

 and more acute. Dorsal margin sloping slightly downward on both sides 

 of the umbo, which is situated a little behind the middle of the hinge-line 

 and points slightly posteriorly. Ventral margin gently curved, and passes 

 gradually to the posterior margin, which is rounded. Hinge-line not quite 

 straight, with about seventeen teeth on each side of the umbo, below which 

 there is a large alivincular pit. Pallial line simple. Lunule large but 

 narrow. A broad but very shallow groove extends from the umbo to the 

 anterior margin. The sculptiire consists of a series of fine concentric 

 grooves with relatively flat and wide ridges between them. 



In my previous paper {Trans. N.Z. Inst., vol. 49, p. 464, 1917) this 

 shell is classified as a species of Mallet ia, a genus which it closely resembles 

 in external form. However, it has the hinge of Yoldia, the pallial line of 

 NucuJa, and the external form of Malletia — peculiarities that Fischer cites 

 as characteristic of Surepta. Several specimens were obtained, some in 

 good condition. 



Type in the Wanganui Museum. 



It may be that this is the species recorded by Hutton from these beds 

 under the name Malletia funiculata, but his specimens seem to have 

 disappeared, and the name is a nomen nudum. 



Sarepta tenuis n. sp. (Plate XV, fig. 9.) 



Shell very small, but thick for its size. Height, 3 mm. ; length, 4 mm. 

 Shape broadly oval. Inequilateral, with a slight anterior extension. Hinge- 

 line a little curved, with seven inclined teeth in front of the umbo and three 

 behind it. Shell somewhat tumid. Umbo prominent. Concentrically 

 striated with shallow grooves leaving low rounded ridges between them. 



A single specimen, in good condition. Differs from >S'. obolella in its 

 shape, its small size, and its concentric ornamentation. 



Type in the Wanganui Museum. 



Limopsis hampdenensis n. sp. (Plate XV, figs. 12, 13.) 



Shell small, sub-rhomboidal, inequilateral, somewhat inflated ; sculp- 

 tured with small rounded concentric riblets about the same width as the 

 interspaces and sensibly granular. On the posterior end from a line with the 

 umbo are numerous well-marked radiating riblets giving the area a distinctly 

 cancellated surface. The disc shows several well-marked periods of rest. 

 Umbones nearer to the anterior end and prominent, slightly project- 

 ing beyond the almost straight dorsal margin. Anterior end short, 

 slightly convex, the curve almost uniform with that of the basal margin. 

 Posteriorly the dorsal margin almost twice the length of the anterior portion, 

 the end truncated, sharply descending, a little oblique, nearl}^ straight, and 

 forming a curve on uniting with the broad upw^ard-sweeping basal margin. 

 Hinge slightly curved ; a narrow triangular pit beneath the apex, and a 

 few small denticles below the teeth, gradually getting larger as they proceed 

 outwards, anteriorly four or five, posteriorly six or seven, and more oblique. 

 Anterior muscle-scar small and inimediately below the hinge-margin, the 

 posterior lower and much larger. The interior shows faint radiations, the 

 margin worn but in places slightly crenulate. Height, 3-5 mm. ; length, 

 4 mm. ; diameter of a single valve approximately 1-25 mm. 



Type in the Wanganui Museum. 



