70 Dynamic Theory. 



CHAPTER VIII. 



EOZOIC AGE. 



PROTOPHYTES FIRST PLANTS. ^ 



v SUB-KINGDOMS. 



PROTOZOA FIRST ANIMALS. } 



The lowest of animal forms is embraced under the title of Sub-King- 

 dom Protozoa, meaning First Life. 



Some of the protozoans are fresh water and others sea water animals, 

 and they may be found in moist places on land. Fig. 7 represents a 

 moneron, and fig. 8 an amoeba. The first is the simplest as it appears 

 to be without a nucleus. The last is simply a minute mass of jelly in 

 which there is a minute granule or nucleus, and it is enclosed in a sack 

 called the ecdosarc or outside skin. This skin has about the consistency 

 of a soap-bubble, and like it can be pierced without being destroyed. 

 The animal gets its food, which consists of minute vegetables, such as 

 diatoms and desmids, through this ecdosarc which closes up and repairs 

 the breach. Effete matters are discharged in the same way. The ani- 

 mal is nothing but protoplasm, the outside of which is slightly differen- 

 tiated into the ecdosarc, and it is without organs of any kind, not even 

 a mouth or an alimentary canal. They propagate by fission. Their 

 locomotion is by the expansion or pushing out of the edge of the body, 

 first on one side then on another, and the contraction of the rest of the 

 body toward the part pushed out. One side or end is just as good as 

 the other for this purpose. 



Another of these amoeba-like animals is the actinophrys. This is a 

 more defined and constant body than amoeba, in this, that the same end 

 generally goes first, and that the same certain parts of his body are 

 likely to be moved to accomplish his locomotion. Otherwise he is ap- 

 parently of as simple an organism as the amoeba. ' Although such an 

 animal, consisting of a bit of slightly modified vegetable protoplasm, 

 was the first to exist, it is obvious that so soft and perishable a body 

 could not be preserved as fossil. 



The lowest fossils are, however, animals of a type but little, if any, 

 higher than the amoeba or actinophrys. They are called foraminifera 

 or rhizopods, eozoa, &c. Each animal is a single cell covered with a 

 thin shell of calcareous matter, which it deposits on its outside, and 

 which remains after the soft parts of the animal have disappeared. 

 Through this shell are minute holes ( foramina ) through which a part of 

 the animal protrudes in minute waving fibres which are called "pseudo- 

 podia" false feet. Sometimes these shells are attached together in 

 masses of various shapes, each cell, however, remaining the house of a 

 single simple animal. 



