FAMILY CHARACTERISTICS. 121 
sylindrical body, as contrasted with the plump, 
compressed body and tapering tail of the Trout 
Family. Or compare, among Insects, the Hawk- 
Moths with the Diurnal Butterfly, or with the so- 
called Miller, —or, among Crustacea, the com- 
mon Crab with the Sea-Spider, or the Lobsters 
with the Shrimps,—or, among Worms, the 
Leeches with the Earth-Worms,— or, among 
Mollusks, the Squids with the Cuttle-Fishes, or 
the Snails with the Slugs, or the Periwinkles 
with the Limpets and Conchs, or the Clam with 
the so-called Venus, or the Oyster with the Mother- 
of-Pearl shell, — everywhere, throughout the Ani- 
mal Kingdom, difference of form points at differ- 
ence of Families. 
There is a chapter in the Natural History of 
Animals that has hardly been touched upon as 
yet, and that will be especially interesting with 
reference to Families. The voices of animals have 
a family character not to be mistaken. All the 
Canide bark and howl: the Fox, the Wolf, the 
Dog have the same kind of utterance, though on 
a somewhat different pitch. All the Bears growl, 
from the White Bear of the Arctic snows to the 
small Black Bear of the Andes. All the Cats 
miau, from our quiet fireside companion to the 
Lions and Tigers and Panthers of the forest and 
jungle. This last may seem a strange assertion ; 
but to any one who has listened critically to their 
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