GEOLOGY AND EVOLUTION. : 93. 
periods he tabulates the fossils of the first division. From this he reports from 
the four sub-kingdoms above named, 366 species. Of these, 264 or seventy-two 
per cent belong to Crustacea, the highest of these ’sub-kingdoms. So while on 
theoretic grounds only the lowest sub-kingdom should have been represented, 
the highest outnumbers all the others by nearly three-fold. In abundance of in- 
dividual specimens, the trilobites, the most common crustaceans, outnumber by 
a hundred-fold all other fossils in the first division of the Bohemian Primordial. 
Barande further states that the families and orders are entirely without transitional 
forms. 
If we examine all the fossils of the Silurian Age, we shall find a somewhat 
similar result. Barande gives 10,074 as the number of Silurian Species known 
and described up to 1872. Of these only 153, or less than two per cent, are Pro- 
tozoans—tr, 306 or thirteen per cent are Radiates, while 2,112 or twenty-one per 
cent are Crustaceans. It will be seen that the highest, though not as numerous 
as the next lowest -sub-kingdom, contains more than both of the lowest two. 
This proportion in favor of the Crustaceans is greater than exists in the living 
species. 
If we examine the number in the classes of the Mollusks we shall find results, 
though not as strong, still in favor of the highest. Cephalopods, the most com- 
plete in organization, are the most numerous. It will also be seen that there is. 
no order or harmony in the number of each class. Placing them in the order of 
their rank we have in number of species and percentage ; 
Cephalopods. . . er NCL OD 2h Noein O07 
Pteropods and Heteropods . Bae RO OMe alia OO 
Gasteropodsueians.: Rie ee ures Saeed 
NEC PIDL Ay ae Wess Niel caine) are qt DOO Op ai anion) + sO, 
Brachtopodsian sneer ste EG O7 oo es 1220 
The EXTREMES are most strongly represented. 
Much has been said about the possibility, that all animal life has been de- 
rived from the Ascidian. If so, it should appear among the earliest fossils. But 
it has never been thus found. It has been asserted that because it has no solid 
parts it could not have been preserved if it had existed. It has a tough leathery 
exterior, far more firm than many an animal found fossilized. We have the im- 
pressions of the soft bodies of spiders preserved in the Carboniferous rocks; and 
185 species of worms have been described from the Silurian. Our marine plants 
found in all geological ages, are of softer texture, yet we find their outlines well 
preserved. Besides,.the living Ascidians are frequently covered by the calca- 
reous material of Bryozoans, which would aid in the preservation of the leathery 
sack. No intermediate form between the Ascidians and the vertebrates exist 
among fossils. The size of many species, eight inches and over, would enable 
them to be easily seen, if only the outline had been preserved. 
To any one who has studied the character and relations of the fossils of the 
various geological formations, it is very clearly discernible, that while the first 
forms are not like the animal life of the present day; they are very far from being 
