TEREBELLA. 195 



is advancing, either from the impression of the light, perhaps, or from 

 the apprehension of danger. 



The sufficiency of the tuhe for accommodation by no means satisfies 

 the tenant, though ample. Like the former, after the temporary repose 

 of the morning, its restlessness is displayed through much of the day, 

 and augmented as evening approaches. At this period an active search 

 for materials commences. Some tentacula secure muddy ladening, others 

 are withdrawing grains of sand, and several seize on shelly fragments. 

 Much industry is manifested, and meantime the various collections approxi- 

 mate merely by contraction of the respective organs retaining them. 

 Amidst this, an undulatory action, apparently unconnected with mere 

 vital functions, like repeated inflation of the upper part of the body, is 

 repeated fifteen or twenty times in a minute, and in an upward direc- 

 tion, as towards the orifice of the tube. Next are small masses of ten 

 or twelve particles discharged within the orifice, perhaps from the mouth, 

 after having undergone some previous preparation there. The under 

 lip seems occupied in smoothing that part up and down, or possibly ce- 

 menting it with glutinous matter. Undoubtedly the materials are swal- 

 lowed. 



During several experiments to obtain a variegated tube, I supplied 

 the large specimen with a quantity of its red native rock, whereon it 

 had been found, now pounded. Next day its body appeared quite red, 

 as if from the quality of the contents. Also, its dwelling hud been 

 augmented. At least two organs or under lips are engaged in preparing 

 the materials, for it is improbable that merely in a crude state they can 

 be adapted for use. During all this the branchiae, however quiescent at 

 other times, are in great activity ; yet without discharging any evident 

 external functions. 



Nothing is more surprising than the attention of so humble an 

 artist, being directed towards such a variety of operations at the same 

 moment. Many tentacula are searching after the materials many in 

 collection many bearing them to the edifice some quitting their hold 

 others recovering the load while the architect itself seems occupied in 



