INFUSORIA. 93 



nished with small- spines covered by a gelatinous substance. 

 The axis of the Gorgonia is also of a homy consistence, 

 and the fleshy matter by which it is covered contains de- 

 tached particles,, that are very friable in nearly the whole 

 species. These are first placed, for an hour or two, in fresh 

 water, and then dried, while the branches are held open. 

 The same method is adopted with the Pennatulae, or Sea 

 Pens. 



There is no difficulty in preserving the calcareous covering 

 of the various Madrepores, &c. ; all that is necessary is to 

 immerse them in fresh water for some hours, so as to extract 

 the salt, and then dry them thoroughly. 



In packing the small kinds, they may simply be placed in 

 cotton ; but the ponderous and heavy ones should be fixed to 

 the bottom of the case which is to contain them. This is done 

 by passing cords between the branches at the base, and bringing 

 these through holes bored in the bottom of the box, and fixed 

 outside with nails. The feet of the Madrepores have some- 

 times large openings, in which case, advantage is taken of 

 them, to introduce pieces of wood into these natural aper- 

 tures, and then nailing them to the bottom of the case. 



We have known many fine specimens of all kinds brought 

 home, by gluing them to the sides and bottoms of packing- 

 boxes ; and, when removed, the packing-box is taken to 

 pieces, and floated in water to moisten the glue, and the speci- 

 mens can easily be taken off. 



Sponges require merely to be soaked in fresh water, and 

 dried. No care is necessary in packing them. 



CLASS XIV INFUSORIA. 



The animals of this Class are only found in infusions, or in 

 water, and are so minute, that they are of no use in a pre- 

 served state. 



