302 



SCIENCE 



[N. S. Vol. XL. No. 1026 



till lately passed for gospel. Destruction 

 may be useful, but it is a low kind of work. 

 We are just about where Boyle was in the 

 seventeenth century. We can dispose of 

 alchemy, but we can not make more than a 

 quasi-chemistry. We are awaiting our 

 Priestley and our Mendeleeff. In truth it 

 h not these wider aspects of genetics that 

 are at present our chief concern. They 

 will come in their time. The great advances 

 of science are made like those of evolution, 

 not by imperceptible mass-improvement, 

 but by the sporadic birth of penetrative 

 genius. The journeymen follow after him, 

 widening and clearing up, as we are doing 

 along the track that Mendel found. 



William Bateson 



MOBPSOLOGY OF TBE BACTEBIA (VIBBIO 

 AND SPIBILLUM), AN EARLY BE- 

 SEABCSA—TEE INTESTINAL 

 FLOBA 

 Biology presents few more fascinating pic- 

 tures than that which portrays the early 

 development of microscopic research in rela- 

 tion to what is now recognized as the science 

 of bacteriology, and in our anxiety to pursue 

 the utilitarian side of the subject it behooves 

 us not to forget the work of the early pioneer 

 naturalists who gave us the first glimpse of 

 the foundation stones of what has come to be 

 one of the most important departments of 

 biological science. Did time permit, I should 

 like to dwell in detail upon the early work of 

 Leeuwenhoek,^ Miiller,^ Bory-de Saint Vin- 

 cent, and later Ehrenberg* and Dujardin," 



1 The research with which this paper deals came 

 to light during a review of the work performed by 

 various authors upon the intestinal flora of men 

 and the lower orders of animals, and it is hoped 

 that the subject will prove of sufficient interest to 

 justify the writer in bringing it to the attention of 

 the Society of American Bacteriologists. 



2 Transactions Boyal Society, 1675-1683. 

 3"Animalia Infusoria," 1773. 



* ' ' Die Inf usionsthierohen als Valkom Organ- 

 ism," 1838; Verhandl. der Berl. Acad., 1839. 

 5"Historie Naturelle des Zoophytes," 1841. 



respectively, 1839-1841 — the latter of whom 

 were the first to attempt a systematic classifi- 

 cation of the bacteria — made doubly difficult — 

 for until this time and for some years later 

 these microorganisms or animalcula, as they 

 were then termed, were included among the 

 Infusoria and were so classified. 



Authorities have credited Perty, 1852, and 

 Robin, 1853, as the first observers to suggest a 

 vegetal nature of these organisms. In a re- 

 cent review of the scientific correspondence 

 between Joseph Leidy and Spencer P. Baird, 

 late secretary of the Smithsonian Institution, 

 in 1847-1849, a letter from Leidy to Baird in 

 1847 attracted my attention. In it he ob- 

 serves that he is in the midst of an investiga- 

 tion upon the structure of the alimentary 

 canal and the chemical processes of digestion, 

 and desires a series of insects from the moun- 

 tainous regions of Pennsylvania, where Baird 

 then lived, upon which to pursue his investi- 

 gation, the results of which he would commu- 

 nicate later through a report to the Philadel- 

 phia Academy of Natural Science. 



Curious to observe the character of this re- 

 search, upon reference to the Academy's Pro- 

 ceedings, we find in October, 18If9, Leidy pre- 

 sented a paper with the following preamble : 



From the opinion so frequently expressed that 

 contagious diseases and some others might have 

 their origin and reproductive character through the 

 agency of cryptogamic spores, which, from their 

 minuteness and lightness, are so easily conveyed 

 from place to place through the atmosphere, by 

 means of the gentlest Zephyr, or even the evapora- 

 tion continually taking place from the earth's 

 surface; and from the numerous facts already 

 presented of the presence of cryptogamic vegeta- 

 tion in many cutaneous diseases and upon other dis- 

 eased surfaces, I was led to reflect upon the possi- 

 bility of plants of this description existing in 

 healthy animals, as a natural condition; or at least 

 apparently so, as in the case of entozoa. Upon 

 considering that the conditions essential to vege- 

 table growth were the same as those uidispensable 

 to animal life, I felt convinced that entophyta 

 would be found in healthy living animals, as well, 

 and probably as frequently, as entozoa. The con- 

 stant presence of mycodermatoid filaments grow- 

 ing upon the human teeth, the teeth of the ox, 

 sheep, pig, etc., favored this idea, and accordingly 



