80 GLASSES. 
guislies them from tlie rest of the ani- 
mal world. 
The second class consists of aves^ or 
birds ; and includes every feathered crea- 
ture, from the tall ostrich to the tiny 
humming bird. 
Lucy, The pretty little humming bhd, 
that hovers over flowers, and sucks the 
honey. — And the third class, mamma? 
Mother, Is the amphibia^ or those 
creatures which possess the power of 
living, with equal facility, on the land or 
in the water, although they chiefly in- 
habit the former. For instance, serpents, 
lizards, and frogs, are amphibious; this 
term being compounded of two Greek 
words*, which signify the capability of 
existing in either element, air or water. 
Lucy. I have often heard of am- 
phibious animals, but I did not before 
know what that expression meant. 
Mother. The fourth class is pisceSp or 
* Amphi, both; Bios, life. 
