FLAGELLATED ORGANISMS IN BLOOD OF HEALTHY RATS. 109 



If it is eventually proved by actual experiments on the nutri- 

 tion of Sponges, that digestion is carried on by the general cells 

 liTiing the passages, and not by the ciliated cells, it is clear that 

 neither the ectoderm nor entoderm of Sponges will correspond 

 with the similarly named layers in the Coelenterata and the 

 Metozoa. The invaginated entoderm will be the respiratory layer 

 and the ectoderm the digestive and sensory layer ; the sensory 

 function being probably mainly localised in the epithelium on 

 the surface, and the digestive one in the epithelium lining the 

 passages. Such a fundamental difference in the germinal layers 

 between the Spongida and the other Metazoa, would necessarily 

 involve the creation of a special division of the Metozoa for the 

 reception of the former group. 



Flagellated Organisms in the Blood of Healthy Rats.^ 

 By Timothy Eichards Lewis, M.B. 



It will be recollected that it is one of the fundamental 

 tenets of M. Pasteur^s creed that neither microscopic 

 organisms nor their germs are ever found in the blood of an 

 animal in health. Doubtless our conception of what implies 

 good health may differ, and especially so when it is the 

 health of an animal, and not of a person, that may be the 

 subject of debate. If it be maintained that an animal affected 

 with either epiphytes or entophytes, with epizoa or entozoa, 

 is not in the enjoyment of full health, then there can be 

 but few perfectly healthy animals. The organs of some 

 animals are almost never absolutely free from parasites. It 

 would nevertheless be scarcely justifiable to pronounce such 

 animals as diseased in the ordinary sense. 



So much being admitted, it is scarcely possible that this por- 

 tion of M. Pasteur's doctrine can be correct. For some years 

 past I have taken considerable interest in this matter, and my 

 attention was drawn to it in a special manner in May last year, 

 by my having been directed by the Government to make inquiries 

 regarding the spirillum of Bombay-fever. Whilst doing this 

 I had occasion to examine the blood of a considerable number 

 of animals, and eventually (July, 1877) detected organisms in 



1 This chapter forms a portion of a paper on "The Microscopic Organisms 

 found in the Blood of Man and Animals," which will shortly be publisiied 

 in the ' Fourteenth Annual Report of the Sanitary Commissioner with the 

 Government of India.' Anotiier portion of this pa[)er, "The Nematoid 

 Hffimatozoa of Man," will appear in the next number of this Journal. — Ed. 



