THE NAUTILUS. 87 



By placing them very close to the glass of the aquarium I was able 

 to observe their movements with some detail. When preparing to 

 move they extend their propodium in an anterior direction, at the 

 same time contracting their metapodium (Plate III, fig. 11). They 

 bend the anterior end of their propodium down into the sand, and as 

 the natural position of the operculum is downward and backward at 

 an angle, when the metapodium is thrust out, the operculum sinks 

 into the sand. With the propodium and operculum as anchors the 

 heavy shell is slid forward (l'late III, fig. 12). Sometimes I have 

 seen them project the end of their metapodium out as far as the tip 

 of the spire. The movement is about an inch and a half per step. 

 The track is represented by a series of little ridges. There is a de- 

 pression on the edge of the lip of the aperture that would on a 

 superficial examination seem to correspond to the anterior siphon 

 canal that is found in many Gasteropods. Through this groove the 

 right eye-stalk protrudes, and the left eye-stalk comes through the 

 true groove of the anterior siphon canal, although no fold of the 

 mantle extends beyond the interior of the shell. (Plate III, fig. 13.) 



The sight of this mollusk is remarked on in almost every account 

 of it. It was my own experience that they would draw within their 

 shell whenever I came within four feet of the aquarium. They also 

 react to a jar. They react definitely when a solid object is passed 

 between them and the source of light. Just how keen their sight 

 really is I was unable to determine. 



All the time I had them in the aquarium I never succeeded in 

 getting one to eat. I tried fresh oyster me"at and oysters that were 

 opened and placed in salt water for two or three days. I also tried 

 raw beef. It is described as a " buzzard among mollusks," but I 

 was not able to observe it feed. When crawling in the sand it 

 swings its proboscis from side to side like an elephant, sometimes 

 dipping the tip into the sand and working its powerful radula. But 

 I could never observe the presence of food of any kind. In the four 

 months I had them in captivity they did not seem to waste away 

 appreciably. 



Strombus is a very interesting mollusk, and would repay study 

 in several fields. Its hardiness assures its easy transportation, and 

 it will live months in confinement. Its eye is wonderfully well 

 adapted to study the histology of the Gasteropod eye, as it can be pre- 

 served without distortion. The large size, abundance and bright colors 

 of the shell make it a conspicuous object on the beach. 



