670 MANUAL OF NATUKAL HISTOEY. 



of invertebrate animals, must be preserved in diluted 

 spirits. By gradually adding the alcohol to the sea- 

 water containing the living specimens, the animals 

 may die in an expanded state, when they should be 

 transferred to some fresh spirit. The same thing 

 may occur if a minute portion of corrosive sublimate 

 is added to the water. 



To capture Infusorial-animalcules or minute phos- 

 phorescent forms, and other microscopic creatures 

 floating near the surface of the sea in calms, sheets 

 of stout bibulous paper should be lowered, raised in 

 a horizontal manner, and afterwards dried and pre- 

 served in a book with the little invisible animals 

 adherent to the papers. 



Sponges and horny and calcareous Corals, should 

 be steeped for a considerable time in fresh-water, 

 to extract the salt, and then dried in a current 

 of air. 



II.— PHYTOLOGY. 



As the collection and preservation of plants, and of 

 vegetable products, are subjects of much importance 

 to the travelling phytologist, it may be advantageous 

 to insert for his use some brief directions when to 

 gather, what to choose, and how to prepare, as the 

 value, both scientific and intrinsic, of an herbarium 

 depends far less on multiplicity of objects, than on 

 the careful selection, and the state of perfection 



