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and boring marine animals. 
most numerous about midway between high and low water 
mark, where the sand is mixed with a large proportion of 
stones. By the shifting of the sands in storms, they are often 
buried to a considerable depth, and at other times have 
several inches of their tubes exposed. In the first case they 
speedily work up to the surface ; in the other, the exposed 
portion of tube is soon broken off by the waves, or crumbles 
when dried by the sun. Their tubes are very long, and the 
animal remains towards the bottom, except when seeking its 
food. Hence specimens are to be obtained in general only in 
favourable situations, as it is almost impossible to dig up the 
whole tube. 
As soon as the Terebella conchilega is removed from its 
tube, it throws itself into spiral folds. This contraction, which 
appears to be involuntary, is effected by the muscular bands, 
which extend the whole length of the ventral surface. The 
dorsal surface therefore constantly forms the outer or convex 
part of all the folds. If now it is placed under water upon 
sand, it straightens the body, and presently all the tentaculae 
are seen in full action. They are extended in every direction, 
often to a length exceeding an inch and half ; and they are 
seen dragging in small fragments of shells, and the larger 
particles of sand. These it places behind the scales project- 
ing from the anterior and lower part of the head, where they 
are immediately cemented by a gluten which exudes from 
the animal ; bending the head from side to side, while it con- 
tinues to apply the materials of its tube, the conchilega has 
very soon formed a complete collar, which it employs itself 
to lengthen regularly from every part of its circumference 
with a persevering activity highly interesting. To fix the 
