340 HABITS OF MOLLUSKS. 



I noticed several species of Melania and Neritina, and 

 one species of Ampullaria. 



During many agreeable boat-expeditions among these 

 islands, I had numerous opportunities of observing the 

 habits of molluscous animals. I shall only add here, 

 however, a few remarks on the Mitra and Calpurnus, 

 reserving other details for the ' Zoology of the Samarang/ 

 where figures of the animals of many species of shells 

 will be published. 



In its habits, the Calpurnus (Ovulum verrucosumj is a 

 very slow-moving, and sluggish mollusk, with all the 

 peculiarities of the Cowries, and exhibits a singularly 

 beautiful and striking appearance under the calm, shal- 

 low water, as it glides tranquilly along the bright sandy 

 bottom. The spots on the mantle are much smaller, 

 and more irregular in form, than those on the foot. 

 The head is pure opaque white, with the exception of 

 one large black spot, placed in the centre of the forepart, 

 which, with its large black eyes, and black-tipped ten- 

 tacles, gives it a very peculiar appearance. It was taken 

 alive by us at the extreme southernmost end of the 

 Island of Mindoro, not far from Ylin, in shallow water, 

 and on a sandy bottom. The Calpurnus appears to be 

 rather numerous among these small islets, though, in 

 other parts of the Philippines, I only met with specimens 

 dead, and thrown up along the beach. 



For a mollusk furnished with such a heavy shell, the 

 Ranella is by no means an inactive animal. It moves 

 with considerable animation, thrusting out its head, pro- 

 truding its tentacles and proboscis, and ascending even 

 perpendicular surfaces with considerable facility. One 



