OCTOBEB 15, 1915] 



SCIENCE 



533 



have also come to be referred to as influenza- 

 like bacilli, have been found especially in the 

 upper respiratory tract in a great variety of 

 diseases. They are frequently met with, for 

 example, in measles, whooping cough, bron- 

 chitis, diphtheria, chickenpox, pulmonary 

 tuberculosis, bronchiectasis, pneumonia, and 

 occasionally, as the writer has shown, in appar- 

 ently normal throats. These bacilli are all 

 very similar, indeed, practically identical, and 

 more recent work seems to indicate that they 

 are also probably identical with the true influ- 

 enza bacillus differing from it only perhaps in 

 respect to virulence. 



Bacilli of this group vary greatly in this 

 respect. As an illustration may be cited the 

 organisms of this type which not uncommonly 

 cause acute meningitis in children. They are 

 found in immense numbers and often in pure 

 culture in the spinal fluid and in the meninges 

 of such patients. They seem to be identical 

 with the true influenza bacilli, having, however, 

 a much higher degree of virulence for animals. 

 In rabbits, for example, after inoculation they 

 may produce death by true septicemia, a result 

 usually not possible to obtain with ordinary 

 doses of Pfeiffer's bacillus.^ 



A further point of interest in connection 

 with all the above bacilli is the fact that when 

 grown on media in the presence of other bac- 

 teria, for example, streptococci, staphylococci, 

 etc., they multiply more rapidly, their colonies 

 are larger and their virulence for animals is 

 increased. In other words, they clearly show, 

 to a marked degree, the property of symbiosis. 



Several other varieties of hemophilic bacilli 

 differing in certain respects and especially in 

 relation to symbiosis have been described by a 

 number of observers. Friedberger^ found in 

 the preputial secretion of dogs such an organ- 

 ism, a very minute, gram negative, non-sym- 

 biotic, non-pathogenic bacillus. Several years 

 ago the writer* described a somewhat similar 

 bacillus isolated from the pathological urine, 

 in three patients in which there was evidence 



2 Cohen, Ann. de I'Inst. Past., 1909, XXIIL, 

 273. 



3 Cent. f. Bakt., I., 193, Orig. 33, p. 401. 



* Jour, of Infectious Diseases, 1910, 7, 599. 



that it had a causal relationship to the infec- 

 tious process, and since then C. Koch^ has de- 

 scribed an identical bacillus which he believes 

 to have been the causal organism in a number 

 of cases of puerperal infection. 



Eecently the writer obtained a bacillus 

 from a large abscess of the shoulder joint in 

 an infant a few months old. Not only cul- 

 tures of pus from the abscess obtained by as- 

 piration, but also cultures of blood obtained 

 from the median basilic vein gave a pure 

 growth of the minute bacillus which was 

 strictly hemoglobinophilic and which re- 

 sembled closely the influenza bacillus in all re- 

 spects except in its symbiotic property. The 

 same bacillus was grown from the bronchial 

 secretion and it was probably from this source 

 that the organism first entered the circulation 

 and later localized in the shoulder joint. 



In the literature there are a few other iso- 

 lated instances where bacteria of this general 

 type have been encountered. 



These bacilli are interesting in that they are 

 pure parasites, for the very evident reason that 

 only in animals can they find the hemoglobin 

 which, so far as we know, is absolutely neces- 

 sary for their existence. And since they are 

 not spore formers and are all very delicate 

 organisms, their length of life outside the ani- 

 mal body is very short, probably a few days at 

 the most. 



The rather remarkable and extreme adapta- 

 tion which they have undergone in relation to 

 hemoglobin is also an interesting and im- 

 portant biological phenomenon. While hemo- 

 globin seems indispensable for their growth 

 certain closely related respiratory pigments, 

 for example, hemocyanin and hemerythrin, 

 which occur in the blood of some of the lower 

 animals and appear to have a function similar 

 to hemoglobin in the higher forms, can not be 

 utilized.^ 



The exact role which hemoglobin plays in 

 their metabolism is not known. They seem to 

 be able to use this substance about equally 



5 Zeit. f. Geburtsh. u. GynoJcol., 1912, LXIX., 

 634. 



6 Davis, J. Inf. Dis., 1907, 4, 73. 



