44 RAMBLES OF A NATURALIST. 



accurately defined characters are admirably adapted 

 for observation. We will follow through all the 

 phases of its existence that large Terebella ( Tere- 

 bella nelmlosa), whose body, which is of a brown 

 colour spotted with red and white, sometimes mea- 

 sures from six to seven inches in length. On its 

 sides are arranged small flattened protuberances, each 

 of which carries a bundle of simple cirrhi, slightly 

 curved, whilst below there is a row of hooked cir- 

 rhi, whose shape somewhat resembles the cock of a 

 gun. On its back, near the head, are six pairs of 

 ramified branchiae, which being incessantly agitated 

 by the blood, alternately present an amber tint or a 

 deep coral red, according as the liquid leaves their 

 branches or flows through their ultimate divisions. 

 From the head escapes a tuft of a hundred to a 

 hundred and fifty white extensile and contractile 

 filaments, which are ever in motion. These are so 

 many living cables, which the animal is able to ex- 

 tend in every direction to the distance of more than 

 a foot, and which serve it in the place of arms. 

 When fixed by their extremities, they enable the 

 Terebella to raise itself along the most highly 

 polished surfaces, as for instance, along the sides of 

 a glass vessel ; at other times, seizing from a distance 

 grains of sand or fragments of shell, they bring 

 them close to the Annelid, and arrange them round 

 the body in the necessary order to enable the animal 

 to take up these substances, and, by cementing 

 them together with a viscid humour, to form a 

 tube or gallery, often of very considerable length, 

 within which it lives in security. 



