VERMES THE WORMS 97 



Around the base of the plumes is a little velvetlike 

 collar, which is the trowel by which the building is 

 effected. 



Plate 35 shows one of each of these worms and their 

 tubes. In the right-hand tube there is a worm on the 

 point of expanding, the little twist of plumes projecting 

 from the top. 



An allied form (Sabellaria) abounds in sheltered situations, 

 forming gravelly tubes, close set together, and cementing 

 the adjacent sand and mud into a concrete. 



Not far removed from these are the Serpulids. The 

 tubes of these are familiar to everyone who has handled 

 a few shells of oyster or scallop. To these, as well as to 

 nearly any other solid object in the sea, these tubes can 

 be seen attached. Unlike those of the sabellids, which are 

 built of a parchmentlike secretion, or of bits of stone, etc., 

 cemented together, the tubes of the serpulids are solid 

 carbonate of lime, like the shells of molluscs. 



Serpula contortuplicata is a familiar example. The tubes, 

 attached by their sides, and often crossing each other or 

 twisted together, may, as I have just said, be seen on nearly 

 all the oyster and scallop shells that come to hand ; but 

 not so well known is the little tube builder. 



This worm is much on the plan of a sabella, save that a 

 part only of the plumes form the funnel or disc ; the others 

 are modified to form a plug, which closes the mouth of the 

 tube when tlje worm retires within. The worms in this 

 species (which is known to naturalists under a variety of 

 synonyms) are of a pale buff colour, and the plumes and 

 Operculum, as the plug is termed, are a bright red. 



There are a great many serpulids, one little one, the 

 name of which is Spirorbis spirillum, abounds on every 

 coast. In some places the fronds of the fucus, and those 

 of the frilled oar- weed (Laminaria saccharina), are studded 

 with them. In this little species the tube is always curled 



