$ome College Series. Tlumber Sebentn-tbree. 



A FEW FACTS ABOUT ZOOLOGY. 



In the air above, the earth beneath, and the waters under 

 the earth, we are surrounded with life. The air swarms 

 with birds, insects, and invisible animalcules; the waters are 

 peopled with innumerable forms, from the microscopic ani- 

 mals, millions of which would not weigh a grain, to the 

 whale so large that, as it sleeps upon the waves, it seems an 

 island; on the earth and in the earth we find life — crawling, 

 creeping, burrowing, boring, leaping, running; life, too, is 

 cradled within life ; in the eyes, liver, stomach, brains, and 

 muscles of animals w r e may find other animals living as par- 

 asites, these parasites many times having parasites living 

 upon them. The earth we tread is largely formed of the 

 remains of life ; the greater part of the Alps, the Rocky 

 Mountains, the chalk cliffs of England, etc., are composed of 

 the shells of microscopic animals, which during past ages 

 have slowly accumulated within the depths of the ocean : 

 from the ruins of this living architecture we build our dwell- 

 ings, churches, and monuments. 



Amid this great diversity of the forms of life there is 

 unity; and this suggests that there is one general plan, but 

 carried out in a variety of ways. " Every animal has some- 

 thing in common with all its fellows ; much with many of 

 them; more with a few; and, usually, so much with several, 

 that it differs but little from them." The object of classifi- 

 cation is to bring together the like, and to separate the 

 unlike. 



Classification. 



A classification, if it be a true one, is not man s work, but 

 his discovery. It is really the interpreting of God's plan in 

 creation. He who gets an insight into that plan may joyfully 



