2G2 THE VOYAGE OF H.M.S. CHALLENGER. 



Area (Barhatia) scitlptilis, Reeve. 



Area aculptilis, Reeve, Conch. Icon., vol. ii. jil. xvii. fig. 118. 



Habitat. — Amboiua, in 15 to 25 fathom.s (C-hallenger) ; Island of Bohol, Philip- 

 jjines (Reeve). 



This species is only a little inequilateral and somewhat stouter at the anterior end 

 than behind. The ventral margin is very feintly sinuated near, but just a trifle 

 posterior to, the middle, and the posterior end is obliquely truncate, the front margin 

 being arcuate. The ligamental area is a little excavated, exhibiting a small diamond- 

 shaped ligament between the over-curving beaks. The surftxce of the valves is finely 

 clathrated, the points of intersection of the radiating and concentric lirse being finely 

 nodose. The radiating ridges display a tendency to be alternately fine and coarser, 

 especially towards both ends of the shell, which in a fresh condition may be described as 

 whitish beneath a thin dirty brownish epidermis. 



Area (Barhatia) pteroesm, n. sp. (PI. XVII. figs. 4—46). 



Testa parva, tenuis, valde ingequilateralis, transversa, subcompressa, antice angustata, 

 acuminata, postice dilatata, oblique truncata, sordide albida, epidermide fibrosa laciniata 

 pallide fusca amicta. Yalvas ajquales, in medio im^Jressione baud profunda ab umboni- 

 bus radianti constrictse, liris radiantibus tenuibus aliisque concentricis flexuosis concinne 

 cancellatse. Umbones parvi, acuti, hand approximati, circiter in ^ longitudinis positi. 

 Ai'ea ligament! angusta elongata adamantiformis, postice angustata. Margo ventris 

 obHquus, antice ascendens, prope medium leviter sinuatus. Pagina interna alba. Linea 

 cardinis gracilis, dentibus circa octodecim miuiita. 



This is a small thin species, veiy inequilateral, narrowed and pointed in front, much 

 dilated and oblicpiely truncated behind at the upper part, and rounded below the 

 truncation. It is dirty whitish, and covered, except at the apices, with a fibrous pale 

 brown epidermis disposed in concentric and overlapping fringes, and produced beyond 

 the edge of the valves. These are rather compressed, and marked with a slight depres- 

 sion which radiates from the umbones to the ventral margin, a little in advance of the 

 middle. The rectilinear dorsal line does not occupy the entire length of the shell. 

 The anterior side is very short, almost at once curving into the obliquely upward- 

 directed ventral margin, which is slightly sinuated at the termination of the oblique 

 depression down the valves. The sculpture consists of fine radiating liras, which are 

 interrupted by numerous, flexuose, concentric ridges or lines of growth, together 

 imparting a somewhat cancellated appearance to the surface. The beaks are only a 



