48 THE PAST CONDITION 



Our next business is to look at the general charac- 

 ter of these fossil remains, and it is a subjeet which will 

 be requisite to consider carefully ; and the first point 

 for us is to examine how T much the extinct Flora and 

 Fauna as a whole — disregarding altogether the succes- 

 sion of their constituents, of which I shall speak after- 

 wards — differ from the Flora and Fauna of the present 

 day ; — how far they differ in what we do know about 

 them, leaving altogether out of consideration specula- 

 tions based on what we do not know. 



I strongly imagine that if it were not for the pecu- 

 liar appearance that fossilized animals have, that any 

 of you might readily walk through a museum which 

 contains fossil remains mixed up with those of the pres- 

 ent forms of life, and I doubt very much whether your 

 un instructed eyes would lead you to see any vast or 

 wonderful difference between the two. If you looked 

 closely, you would notice, in the first place, a great 

 many things very like animals with wdiich you are 

 acquainted now : you would see differences of shape 

 and proportion, but on the whole a close similarity. 



I explained what I meant by Orders the other day, 

 when I described the animal kingdom as being divided 

 into sub-kingdoms, classes, and orders. If you divide 

 the animal kingdom into orders, you will find that 

 there are above one hundred and twenty. The num- 

 ber may vary on one side or the other, but this is a 

 fair estimate. That is the sum total of the orders of 

 all the animals which we know now, and which have 

 been known in past times, and left remains behind. 



Kow, how many of those are absolutely extinct ? 

 That is to say, how many of these orders of animals 

 have lived at a former period of the world's history, 



