420 General Biology 



animals having a soft body have decayed and left no record of themselves 

 among the fossil remains thus far found. Only those which possessed 

 an intensely hard substance, or lived and died in regions where, due to 

 the peculiar character of the soil or water, they were preserved, can 

 furnish us with any accurate record of the past. 



There are men who have taken up individual studies in order to 

 ascertain all the details of their given specialties, and such men are 

 named after the study-group they have adopted as such specialty; for 

 example, one who specializes in the study of protozoa is called a Proto- 

 zoologist; one who studies worms is known as a Helminthologist ; one 

 who studies mollusks, a Conchologist ; one who studies insects, an 

 Entomologist, while he who studies birds is an Ornithologist, and he 

 who studies mammals, a Mammalogist. 



It is, of course, understood that these men may not be interested in 

 classification alone, but that they may be anatomists, physiologists, 

 ecologists, etc., also in regard to their favorite study. 



The checking up of the different conclusions which different workers 

 in the same field, and different workers in different fields, have arrived 

 at, is one of the most interesting and valuable studies possible. This is 

 particularly true, because so frequently all the evidence that a Paleon- 

 tologist accepts, points to a totally different conclusion from that which 

 the student .of experimental genetics finds to be true. The history of 

 science is replete with cases of groups of men having held and defended 

 doctrines most valiantly, and with seeming correctness, entirley opposite 

 to those of men in other fields of study. 



References. 



Schull, "Principles of Animal Biology." 



H. C. Oberholser, "The Nomenclature of Families and Subfamilies 

 in Zo61ogy." "Science," August 13, 1920. 



TABULAR VIEW OF THE CLASSIFICATION OF ANIMALS AS 



FAR AS ORDERS 



(After Hegner, Schull, Handlirsch, Brues, Melander, Muttkowski, 



and Wheeler.) 



PHYLUM I. PROTOZOA 

 Class I. Rhizopoda ( ) 



Order 1. Lobosa ( ) 



Order 2. Heliozoa ( ) 



Order 3. Radiolaria ( ) 



Order 4. Foraminifera ( ) 



