108 BY THE DEEP SEA. 



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attributes of the humble sea-worms. Let us look at a few 

 representative forms. 



Flat, or nearly flat rocks that are only uncovered by the 

 recess of the spring tides, will often be found to be strangely 

 coated with coarse sand in which are immersed round tubes 

 with their mouths protruding. This is a colony of the com- 

 mon Sabella (Sabella alveolaria), which cements the sand 

 together in long tubes, and appears also to spill some of its 

 liquid glue around ; for the spaces between the tubes are filled 

 with sand similarly agglutinated, so that the whole surface of 

 the rock is uniformly coated with sand in which are the 

 sabellae-tubes. There is nothing to see, so long as the sea 

 remains out ; but when the incoming tide covers this rock it is 

 a sight worth seeing. From every one of these tubes there 

 comes forth a plume of feathers in shape like a funnel. The 

 tubes are fashioned by curiously-modified antennae, which 

 serve the purpose of a couple of trowels to manipulate the 

 material that has been scooped up by another organ, to mould 

 and smooth it, and make it comfortable for habitation. 



Its methods of working can be clearly seen by capturing a 

 specimen or two, evicting it from its home, and placing it in a 

 glass vessel with a little clean sand on the bottom. It will 

 immediately proceed to the elaboration of a new tube ; and 

 with that eye for economy of labour and material which 

 characterises the majority of natural builders, it will make the 

 glass serve as the base of its tube, and thus reduce its labour 

 by a third. 



The breathing organs (branchice] of these tube-masons are 

 external, and form a very beautiful object when the worm lies 

 on the threshold of his house and pushes this apparatus out, 

 that his blood may benefit from the abundant oxygen of the 

 ever-moving waters. At first the branchial plume issues very 

 cautiously and with slight pauses and withdrawals ; but find- 

 ing all safe the Sabella at length gets it quite out and expands 

 it to its glorious fulness, delicate in structure, splendid in 



