172 THE VOYAGE OF H.M.S. CHALLENGER. 



The Challenger specimen is somewhat differently coloured from that figured by Reeve. 

 The spines on the hinder part are white, set upon a rich red ground, those upon the anterior 

 half of the upper valve being lightish brown at the tips and white at the bases. In this 

 species the lower valve is angulated down the middle, half, or a little more, being 

 attached and the remainder arising at an oblique angle. The umbo in this valve is 

 considerably curved over towards the front and away from the dorsal edge, but not 

 nearly to the same extent as in Chama multisqxiamosa, an allied form. The interior of 

 this valve is generally whitish in front, and more or less stained with purple-rose or 

 purple-browTi upon the hinder portion or non-attached half The upjaer valve has usually 

 less colour within, generally exhibiting a more or less distinct purplish stain from the 

 umbo down the hinder central part and some purplish spots upon the outer margin. The 

 spines upon the exterior of the lower valve vary in colour, being either white, brown, 

 yellow, or pinkish. 



Chama carditceformis (P), Reeve. 



Chama carditceformis, Eeeve, Conch. Icon., vol. iv. pi. vi. fig. 33. 

 Habitat. — Statipn 208, Philippine Islands, in 18 fathoms ; blue mud. 



The type of this species in the British Museum has been very much over-cleaned, and 

 the spines to a great extent worn down so that it is imjjossible to pronounce ^dth cer- 

 tainty whether the j)retty little specimen from the above locality be without doubt 

 conspecific. It is of the same Cardita-\\\.e form, but has a p)eculiar colouring. The 

 short hollow spines in the free valve, which radiate in series from the umbo, have a 

 pinkish-red spot within at their bases, which are only seen when the shell is placed in a 

 certain position. The apices of both valves are pink, and the interior of the upper valve 

 exhibits a broad brown stain upon the hinder half. The figure in the Conchologia Iconica 

 is far from correct, the spines down the posterior side being greatly exaggerated. 



Chama jukesii. Reeve. 



Chnma juliesii, Eeeve, Conch. Icon., vol. iv. pi. vii. fig. 39. 

 Habitat. — Station 186, off Cape York, North Australia, in 8 fathoms ; coral mud. 



The type of this species in Cuming's collection was collected by Mr. J. B. Jukes at 

 Cape Upstart, also on the north coast of Australia. I cannot discover any good reasons 

 for separating either Chama pellis-phocce or Chama fibula (both of Reeve) from this 

 species. 



