3996 Mollusks. 



inch of the sand, then hangs suspended as if surveying the ground for 

 a suitable bed. Presently it selects a spot; the first indication of its 

 choice being that a hollow about the size of a silver fourpence is for- 

 cibly blown out of the sand immediately beneath the group of pendent 

 arms. Into the cavity so made the little animal drops; at that instant 

 the sand is blown out on all sides from beneath the body backward, 

 and the abdomen is thrust downward before the cloud of sand which 

 has been blown up settles, but which presently falls around and upon 

 the body. Another forcible puff in front, one on each side, and ano- 

 ther behind, follow in quick succession, the fine sand displaced at 

 each blast settling round the animal, as it thrusts itself into the hol- 

 low thus more and more deepened. 



I was not at first quite sure by what agency these blowings, so ad- 

 mirably effective and suited to the purpose, were performed. The jet 

 in front I readily attributed to the action of the fleshy funnel project- 

 ing from beneath the mantle on the breast ; but I did not see how 

 this could blow a stream directly backwards. I therefore put one of 

 my pets into a vessel with glass sides, which was furnished with the 

 requisite sand and water. I at once saw that the funnel was indeed 

 the organ employed, and the only one in every case ; and perceived 

 its beautiful adaptation for the work it had to do, in its extreme 

 flexibility. This organ is very protrusile, and being perfectly flexible, 

 its orifice can be, and is, at will pointed in any direction, so as to 

 blow the jet of water forward, backward, or to either side at pleasure. 



It frequently occurs, of course, that small stones are mingled with 

 the sand, or the animal may find it convenient to burrow in the loose 

 gravel. In either case the arms come to the aid of the funnel, the 

 sucking disks with which they are furnished being made to adhere to 

 the stones, which are dragged out and thrown aside. You may sup- 

 pose this to be a clumsy expedient, but you would think differently 

 if you saw it : the rapidity with which the arms are thrust under the 

 body, and drawn out, bearing pieces of stone of comparatively large 

 size, and the graceful ease with which they are then thrown forward, 

 discharging and dropping the burden, impress the mind with admira- 

 tion of the beautiful fitness of the organization for the requirement. 



This use of the funnel, and of the sucking arms, so different from 

 their normal purpose, affords additional examples of that Divine eco- 

 nomy in creation, which, when a new function is ordained, does not 

 always form new and special organs for the necessity, but adapts some 

 already employed in other service for the new work ; while, still, both 

 the one and the other function are fulfilled with such perfection, as 



