INTRODUCTION 9 



and which are found as fossils. They are Foraminifera and Ra- 

 diolaria. From early palaeozoic times down to the present day, 

 the carbonate of lime which makes up the skeletons of numerous 

 Foraminifera has been left embedded in various rock strata. Al- 

 though there is no distinctive foraminiferan fauna characteristic 

 of a given geologic period, there are certain peculiarities of fossil 

 Foraminifera which distinguish one formation from the other. 

 From this fact one can understand that knowledge of foraminifer- 

 ous rocks is highly useful in checking up logs in well drilling. The 

 skeletons of the Radiolaria are the main constituent of the ooze 

 of littoral and deep-sea regions. They have been found abun- 

 dantly in siliceous rocks of the palaeozoic and the mesozoic, and 

 are also identified with the clays and other formations of the 

 miocene. Thus knowledge of these two orders of Sarcodina, at 

 least, is essential for the student of geology and paleontology. 



The history of protozoology 



Aside from a comparatively small number of large forms. Pro- 

 tozoa are unobservable with the naked eye, so that we can easily 

 understand why they were unknown prior to the invention of the 

 microscope. Antony van Leeuwenhoek (1632-1723) is commonly 

 recognized as the father of protozoology. Grinding lenses himself, 

 Leeuwenhoek made more than four hundred microscopes, includ- 

 ing one which, it is said, had a magnification of 270 times (Hart- 

 ing). Among the many things he discovered were various Proto- 

 zoa. According to Dobell (1932), Leeuwenhoek saw for the first 

 time in history, free-living Protozoa in fresh water in 1674. Among 

 them, he observed bodies "green in the middle, and before and 

 behind white," w^hich Dobell interprets were Euglena. Between 

 1674 and 1716 he apparently observed numerous microscopic or- 

 ganisms which he communicated to the Royal Society of London 

 and which, as Dobell considered, were Vorticella, Stylonychia, 

 Carchesium, Volvox, Haematococcus, Coleps, Kerona, Antho- 

 physa, Elphidium, Polytoma, etc. According to Dobell, Huy- 

 gens gave in 1678 "unmistakable descriptions of Chilodon(ella), 

 Paramecium, Astasia and Vorticella, all found in infusions." 



Colpoda was seen by Bouonanni (1691) and Harris (1696) re- 

 discovered Euglena. In 1718 there appeared the first treatise on 

 microscopic organisms, particularly of Protozoa, by Joblot who 

 emphasized the non-existence of abiogenesis by using boiled hay- 



