leproma, in symbiosis with cholera and amœba, it is doubtful whether any success had been met with in the artificial cultivation of this organism, and certainly no one has been able to carry cultures on for several generations.

The following brief review of the literature on this subject is, however, of interest as showing the difficulties met with in the attempts to cultivate this organism and by showing the futility of attempting to grow this bacillus on ordinary media, and thus prepared the way for its final successful cultivation.

Neisser (2), 1886, attempted to cultivate the bacillus on gelatinblood serum and cooked egg. He thought that slow multiplication occurred on these media, but his experiments were not productive of any practical results.

Bordoni-Uffreduzzi (3), 1887, first reviews the work of previous investigators in their attempts to cultivate the bacillus of leprosy. quoting Fraenkel as stating that heretofore no success had been met with in growing this bacillus on artificial media, and also stating that Fluegge (Die Mikroorganismen, usw., 1886, 2. Aufl., p. 221), Hansen (Virchow's Archive, 1882, vol. 90, p. 542), Neisser (2), and Crookshank (Manual practique de bacteriologie, Trad. par Bergeaud, Brussels, 1886) had been entirely unsuccessful in their attempts at growing this organism outside of the body.

Bordoni-Uffreduzzi then goes on to describe his own cultural attempts. He uses as media bouillon, gelatin, agar-agar, and coagulated blood serum, as well as spinal marrow, on peptone-glycerin serum; on the latter media he secured a growth of what he thought was the lepra bacillus.

The same author (4), 1887, describes the organism which he grew from leprous material on spinal marrow media, and his description seems to indicate that the bacterium is one of the nonacid-fast diphtheroid group.

The same author (5), 1888, replies to certain criticisms of Baumgarten regarding his organism, and attempts to uphold his claim of having cultivated the bacillus of leprosy.

Baumgarten (7), 1888, sums up, in a manner unfavorable to the claims of Bordoni-Uffreduzzi, the controversy over the bacillus grown by that investigator.

Beavan Rake (8), 1888, employed the serum of lepers either as a fluid or solidified with agar or gelatin. On these media he grew a number of organisms, but none of them were acid fast.

Gianturco (9), 1889, employed glycerin agar and cultivated what appeared to be a similar organism to that isolated by BordoniUffreduzzi, and he believes his bacillus to be identical with BordoniUffreduzzi's organism.

Bordoni-Uffreduzzi (10), 1889, agrees with Gianturco that they have isolated identical organisms.

Campana (11), 1889, describes 500 attempts which he made to grow the bacillus of leprosy on artificial media, all of which, however, resulted in failure, and from this experience he doubts the claim made by other investigators that this bacillus could be grown on certain artificial media.

Beavan Rake's (12), 1891, work is reviewed in an editorial of the Lancet, 1891, and the statement made that all of this investigator's attempts have proven negative.

Holst (13), 1891, believed that failure to cultivate the bacillus of leprosy was due to the organisms in old lepromata being dead. He therefore chose only new nodules in his work, thus hoping to secure live bacilli; his attempts at artificial cultivation were, however, entirely negative.

Campana (14), 1891, isolated an anaerobic, nonacid-fast bacillus from a leproma and believed this organism to be the bacillus of leprosy.

Kanthack and Barclay (15), 1891, employed bouillon and glycerin agar for media and were successful in growing an acid-fast organism from a leproma. This peculiarity of acid fastness appeared to be variable, however, as after growing for some time on artificial media it became almost nonacid fast, and still later regained its acid fastness. These investigators were at first inclined to consider this organism to be B. lepra, but in a subsequent communication they withdrew this claim.

Campana (16), 1891, describes further culture peculiarities of the bacillus which he isolated.

Ducrey (17), 1892, isolated a bacillus, probably identical to Campana's bacillus, from a leproma, and found that, like Campana's organism, it was very little, if at all, acid fast.

At the "Lepra Discussion" (18), 1892, the organism isolated by Campana was discussed.

Campana (19), 1892, again discusses the method he employed in the cultivation of an anaerobic nonacid-fast bacillus from a leproma. Wolters (20), 1893, reviews some of the cultural attempts made to date and judges all previously reported successes to be either doubtful or negative. He himself thinks that he once secured, while work ing in Doutrelepont's clinic, a single B. lepra colony on glycerin

agar.

A commission composed of Beavan Rake, Buckmaster, and Thomp son (21), 1893, report attempting to grow B. lepra on various media, but that they only succeeded in growing a liquefying, non

acid-fast bacillus.

Campana (22), 1894, describes the morphology of the bacillus which he isolated (previously referred to). The media he employed was agar, mixed with bouillon, peptone, and glucose. The organism grows anaerobically and is neither alcohol nor acid fast.

Levy (24), 1898, succeeded in growing an organism on glycerin agar from the blood of a leper. This organism is nonacid fast, or very slightly acid fast. With this rather important exception, it resembled "the bacillus of bovine tuberculosis," or possibly a streptothrix.

The same author (25), 1898, again refers to the organism which he grew from a leper. He considers that it is a streptothrix and probably identical to Czaplewski's organism. He considers this organism of only academic interest, and not B. lepræ.

Czaplewski (26), 1898, grew from the nasal secretion of a leper an organism which he believes belongs to the "Sklerothrixgruppe.” This organism retains its acid fastness in cultures. He denies the claim of Levy that this organism is identical with Levy's and therefore a streptothrix.

Spronck (28), 1898, succeeded in growing a bacillus from a leproma, using glycerin-potato as media. This organism, from his description, appears to be a member of the pseudo-diphtheria group.

Levy (29), 1899, again writes on the organism which he isolated from a leper, and still believes it to be a streptothrix. He mentions Babes, Spronck, and Czaplweski as having grown the same organism as himself, while, on the other hand, Bordoni-Uffreduzzi's, Gianturco's, and Campana's publications deal, in his opinion, with a different organism.

Teich (31), 1899, claims to have grown an acid-fast, pleomorphic organism from five cases of leprosy. He used potato agar as a media.

Bordoni-Uffreduzzi (32), 1899, reviews what he considers his successful attempt to grow the bacillus of leprosy, and states that Gianturco, Spronck, Czaplewski, and Barannikow all later grew the same organism, and all regarded it as an acid-fast bacillus.

Babes (33), 1899, refers to a previous article (Zeitschrift fuer Hygiene, 1889, February, p. 173) and to Czaplewski's description (Centralblatt für Bakteriologie, etc., Originale, No. 13, 1898), also to the work of Cornil and Babes in 1890. In his present article Babes gives a full description of an organism which he previously isolated, and which he believes belongs to the pseudo-diphtheria group. In his cultures he occasionally observed branching forms. He has succeeded in isolating this organism from the nodules of 12 lepers.

Barannikow (34), 1899, grew a bacillus from a leproma, which resembles the organism of Babes, Bordoni-Uffreduzzi, and others; that is to say is a member of the pseudo-diphtheria group.

Carrasquilla (34a), 1899, grew what he believed to be lepra bacilli on coagulated human serum. The organism was motile and aerobic.

Kedrowski (35), 1900, used placenta for media, and succeeded in growing four different varieties of streptothrix, all of which were more or less completely acid-fast.

Scholtz and Klingmüller (36), 1900, reported complete failure to grow the bacillus of leprosy, and express the opinion that no one else had succeeded up to that time.

Puschtiwoi (37), 1902, used potato as media, and by this means succeeded in isolating a bacillus from a leper. No description of this bacterium is given in the abstract of this article in "Lepra Bibliotheca Internationalis," and his original article is inaccessible

to us.

Van Houtum (38 and 38a), 1902, attempted to cultivate the bacillus of leprosy on various media, and states that he found that by starting his cultures on fish bouillon, containing a small portion of beef bouillon, the organism multiplied. From the abstract (Lepra Bibliotheca Internationalis, vol. 5; the original article is inaccessible to us) it appears that he then transferred this bouillon culture to glycerin-glucose-agar slants, on which latter media the organism he was dealing with grew well. The bacillus he isolated was nonacidfast and liquefied gelatin.

Kedrowski (39), 1902, has grown a number of branching forms of either streptothrix or other higher forms from leprous nodules. He employed as a media an extract of placenta which, after sterilization by filtration, was added to agar.

Barannikow (40), 1902, grew a nonacid-fast bacterium from a leproma and believed it to be B. lepræ.

Zenoni (41), 1902, claims to have cultivated a nonacid-fast bacillus from the skin lesions of a leper. This bacterium caused the death of white mice in from 2 to 13 days.

Levy (42), 1902, claims that after growing on garden beets for one generation his organism will grow on glycerin bouillon, and on this latter media it resembles the bacillus of diphtheria.

Gjubert (43), 1903, employed, as media, calf's brain emulsion in agar, and reports what he believed to be a successful attempt to cultivate B. lepræ.

Zenoni (45), 1904, states that the "best" artificial media for the cultivation of the lepra bacillus is the serum of lepers, inactivated at 55° C. By employing this media he succeeded in growing a nonacid-fast organism, apparently belonging to the pseudo-diphtheria group. He inoculated white rats with this organism and caused lesions which, in his opinion, resemble human lepromata.

Rost (46), 1904, prepared numerous salt-free media, and on these believes he succeeded in growing B. lepro.

Rost (47), 1905, reiterates his claim that lepra bacilli will grow on salt-free media, the growth appearing in bouillon, freed from sodium chloride, from three to five days after inoculation with leprous material. He uses his cultures to obtain an extract for therapeutic purposes.

Editorial, Lancet (48), 1905, refers to Semple's work disproving Rost's claim to have grown the bacillus of leprosy.

Weil (49), 1906, employed several media, among which were glycerin-glucose agar, containing noncoagulated, human pleuritic serum; glucose peptone agar, containing noncoagulated, human pleuritic serum; live hen's egg, etc. On several of these media, but especially on the hen's egg, this investigator thought he was successful in securing a growth of the bacillus of leprosy for one generation. The growth was stated to begin on the fifth day, proceed up to the twenty-fifth day, after which no further development occurred. The colonies produced were of a light-yellowish color. Weil did not succeed in transferring these colonies beyond the first generation. Campana (51), 1909, describes again the bacillus which he grew from a leper, under anærobic conditions, on glucose media.

Clegg (52), 1909, grew amoeba and S. cholera in symbiosis on plain agar and weakly nutrient agar. The amoeba which he employed were obtained from several sources (animals' intestinal tracts and pond water). To these two symbiants, when growing well together, leprous material was added. A few days after this addition morphological changes were seen to occur in the lepra bacilli, the long slim rods noted in tissues became beaded, and from the deeply stained portions of these beaded bacilli short, plump rods developed. By further multiplication chains longer than the original clumps, composed of many short bacilli, were noted in the culture media. After this morphological change had occurred, multiplication continued. At the end of a week or 10 days transfers were made to plain agar tubes, and this process of transfer continued until he secured multiplying subcultures 10 or more generations removed from the original inoculation. These later generation tubes contained many more acid-fast bacilli than the original tube, showing that multiplication had occurred. At the time this first paper was written Clegg had not isolated the acid-fast organism in pure culture.

Clegg (53), 1909, since writing the last article, continued his experiments on the artificial cultivation of the leprosy bacillus in symbiosis with S. cholera and amoeba, and at the time of writing this article had succeeded in growing acid-fast bacilli seven times from as many cases of leprosy. All of these seven cultures were grown in symbiosis with amoeba and cholera. The cultures were secured from as unlike sources as the skin nodules of a living leper and the spleenic pulp of a dead leper.