420 THE SABELLA. 



set to work with hammer and chisel to cut out the 

 rock around them. The hollow was breast-high in 

 the side of a great mass of rock, so that it was easy 

 to work at it ; the shale too was fortunately very soft 

 and friable. In about an hour we had cut away the 

 surrounding parts to the depth of five or six inches, 

 when the laminae of the shale came away piecemeal, 

 with the tubes adhering by the side to them. The 

 membranous matter, of which the tubes are formed, 

 and which is, I have no doubt, an exudation from the 

 skin of the animal, was spread about upon the surface 

 of the laminae on each side of the adherent tube. 

 What was particularly interesting was that some of the 

 tubes had a family of young ones attached to them. 

 These were of different ages, and their little slender 

 tubes were creeping in irregular directions along the 

 parent tube, from the thickness of a hog's bristle to 

 that of a goose-quill. The young tubes are not 

 straight, but bent at various angles, adherent to the 

 parent for the greatest part of their length, but free 

 at the anterior extremity, where a tuft of plumes pro- 

 trudes. The feathery crown does not differ from that 

 in the adult essentially, but consists of fewer plumes 

 in the ratio of age, and these are pure white to their 

 base. The youngest that I can find, inhabiting a 

 tube about as thick as a bristle, and half-an-inch long^ 

 has a simple brush of five or six filaments, in the 

 form of a concave fan, the middle plumes being the 

 longest. Another, with a tube about as thick as a 

 stout pin, has thirteen, and one, as thick as a wheat- 

 straw, seventeen plumes, arranged in each case in a 

 simple funnel-like circle. 



