i86 TOILERS IN THE SEA. 



club, sometimes oval or oblong, with the surface 

 ornamented with more or less complex bosses or pro- 

 jections (Plate IV.). Certain authors believe that they 

 can determine the genus, even if not the species of 

 the family of Gorgonia, from the form of their cal- 

 careous spicules, which, at the least, must be accepted 

 as implying that, although the forms vary in the 

 spicules of different species, they are at the same time 

 constant in each of the species. 



It may be intimated here that the spicules of these 

 organisms may be easily removed from the bark, and 

 cleared of all extraneous matter, so as to be mounted 

 permanently as " objects for the microscope." A small 

 portion of a branch, or of the cortex from a branch, 

 may be boiled in a test-tube, with liquor potasscz, for a 

 minute or two, and when cool and settled, the sedi- 

 ment may be washed by shaking in water, allowed to 

 settle, the water poured away, and more water added, 

 shaken again and again allowed to settle, as often as 

 need be, and the final sediment will be found to be 

 the clean spicules which may be mounted dry, or 

 immersed in Canada balsam. Some prefer to mix 

 spicules of different forms and colours together, 

 others to keep each kind separate and distinct ; let 

 every one be persuaded in his own mind. 



M. Valenciennes, who wrote a monograph of this 

 family, has classified the forms of spicules in the 

 following manner : 



