SABELLA. 257 



ture*. To catch aud collect the muddy material necessary for the 

 work, the branchial fans are spread out into a semicircle, so that 

 when the two are brought into contact a wide funnel is formed. 

 Once in the funnel the muddy water is forced down the rachis of the 

 filaments by the play of the ciliary fringes, and brought within reach 

 of the singular organ at the base of the funnel by which the mud is 

 selected and applied, just as a mason would lay lime on with his 

 scoop, and then mould and smoothen it with his trowel. This 

 beautiful organic apparatus was first noticed by Sir J. G. Dalyell. 

 At the base of the funnel, and towards one side, are two external 

 fleshy lobes or trowels with an organ like a tongue or scoop between 

 them. Receiving the pellets of mud, the creature mixes it up with 

 an adhesive secretion furnished probably by the collar of the cephalic 

 segment and by the organs just mentioned. It is thus rendered 

 consistent and tenacious, and fit to be employed in raising the edge 

 of the tube. To that position the material is raised by the tongue 

 and trowels, aided by a general elevation of the head ; and it is 

 fashioned into shape by the same tongue and trowels curved over the 

 exterior circumference as far as they can be stretched, and smoothed 

 and polished by their motions while clasping it with their pressure. 



And thus the tube is built up. The lower portion has been left 

 unoccupied, for it has become too straight for the tail, which has 

 grown with the worm's growth ; and the upper portion extends far 

 beyond what may at first seem necessary, but its Creator foresaw 

 that it was needful this lower work of His should be able at pleasure 

 to hide the glories with which he has adorned it, — otherwise too 

 seductive to the enemies that were enticed by the richness of the 

 display. For its tube the worm seldom uses other material than 

 soft mud, but in urgent need fine sand may be partially resorted to. 

 The gummy fluid with which it is cemented is, in the first instance, 

 undoubtedly supplied by organs connected with the head ; but much 

 is afterwards furnished by the skin of the body to make the interior 

 more consistent and lubricous. Indeed, that the tube may be kept 

 circular throughout, the worm is, while working, in a state of con- 

 tinual rotation, — " a slow revolution, the body passing around within 

 the tube." "Let a tall and ample crystal jar," says Sir J. G. Dalyell, 

 " containing an Amphitrite, be emptied of its contents, and speedily 

 replenished with sea-water, — the animal, if in view, has retreated 

 during the short interval ; the orifice of the tube is closed ; all is at rest. 

 But soon after replenishment, it rises to display its branchial plume 

 still more vigorously than before, and remains stationary, as if enjoy- 

 ing the freshness of the renovated element, always so grateful, — the 

 harbinger of health and strength to those whose dwelling is there. 

 The passing spectator wovild conclude that he now beholds only a 

 beautiful flower, completely expanded, inclining towards the light, 

 like some of those ornaments of nature decorating our gardens. He 



* " The welfare of the animal is dependent on fixture, otherwise it is totally 

 helpless ; neither, until the extremity be secured, does the Amphitrite usually 

 venture to show itself. Sometimes the renovated part of tlie sheath extended an 

 inch or more at the bottom of the vessel, which being attained, all subsequent 

 care seemed to be devoted to the opposite extremity about the orifice." — Dalyell, 



s 



