590 TREPONEMATA, SPIRONEMATA, LEPTOSPIRATA 
non-syphilitic lesions as well, particularly in superficial lesions of the 
genitalia. This association of Spironema refringens with Treponema 
pallidum in syphilitic lesions and its common occurrence in non- 
specific genital lesions emphasizes the necessity of its recognition and 
dift'erentiation from Treponema pallidum. 
Morphology.— Observed under the dark-field microscope, Spironema 
refringens is noticeably thicker than Treponema pallidum, measuring, 
according to Noguchi,i 0.5 to 0.75 micron in diameter and 6 to 24 
microns in length. The ends are somewhat sharply attenuated and 
they are continued as moderately stiff, delicate spiral flagella. Not 
infrequently the middle third of the organism is slightly wavy in out- 
line, the end thirds being more closely coiled. Usually the spirochetes 
are more uniformly curved. Occasionally two or three organisms may 
be joined end to end. As a rule there are from 3 to 8 complete spirals 
in each organism. 
The organisms are actively motile, and observed with the dark- 
field illumination they are golden-yellow, contrasting in this respect 
with the pale yellow appearance of Treponema pallidum. The staining 
reactions are similar to those of Treponema pallidum. 
Isolation and Culture. Xoguchi was the first to grow Spironema 
refringens in pure culture using the agar ascitic fluid tissue medium 
with which he isolated Treponema pallidum. The organism is a 
strict anaerobe, but it may be obtained in the agar ascitic medium 
without the sterile tissue, although the growth is much more feeble 
when the tissue is omitted from the medium. The original growths 
from lesion to artificial media are usually contaminated with other 
organisms. Purification is accomplished by the same technique as that 
used for purifying Treponema pallidum. Pure cultures of Spironema 
refringens produce no odor in growths on artificial media. 
Pathogenesis.— The organism was found to be non-pathogenic for 
rabbits and monkevs.- 
SPIRONEMA PHAGEDENIS. 
Synonyms.— Spirocheta balanitidis; Treponema phagedenis. 
Schaudinn and Hoffmann,^ Miihlens,^ Hoffmann and Prowazek^ 
and others have described spiral organisms resembling Treponema 
refringens in size, shape and motility in genital and perigenital ulcera- 
tions and in phagedenic ulcers. Similar organisms have been observed 
in noma. Corbus and Harris*' and Corbus^ have described a spiral 
organism resembling Vincent's spiral in several cases of erosive and 
gangrenous balanitis, and Brault** has observed a similar spiral asso- 
' .Jour. Exp. Med., 1912, 15, 467. 2 ibid., 90. 
' Arb. a. d. kais. Gesamte, 1905, 22, 527. 
< Deutsch. med. Wchnsehr., 1907, 33, 1207. 
s Centralbl. f. Bakteriol., orig., 1906, 41, 741, SIS. 
« .Jour. Am. Med. Assn., 1909, 53, 1474. " Ihid., 191:^, 60, 1769. 
« Bull, dermat. et syph., 1908, p. 2. 
