﻿ETIOLOGY OF MYCETOMA. 481 



instances ni3 r celial threads may be seen. The alteration in tissue in sec- 

 tions from many other places in the foot is so great as to render the 

 differentiation of the various elements impossible. 



The whole foot is practically a mass of degenerated tissue, debris, 

 and fungus elements, in which an occasional, recognizable piece of nerve, 

 bone, or tendon may be seen. There are areas of fixed tissue-cell prolif- 

 eration, in places usually surrounding a partially occluded blood vessel 

 or a granule of the fungus mass. Evidences of repair of tissue or of 

 acute inflammation are almost entirely absent. The Streptothrix is 

 found in the sections in the form of granules and of occasional mycelial 

 threads, both of these types being evident in masses of debris lying in 

 somewhat definitely outlined cavities, and again among better preserved 

 tissue cells. The granules vary in size from about 25 jx to 5 millimeters 

 or more, and although they usually are oval or round in the smaller 

 masses, they are of dumb-bell or more irregular shapes in the larger ones. 

 The smaller granules, when appropriately stained, appear as conglomerate 

 masses of mycelia, like puffballs, in which degenerated cells, crystals, 

 and unstainable debris may be embedded; the margins of these granules 

 often show a more or less definite radiation of fibers from the central 

 mass, coccoid and other irregular forms being rare. The picture is 

 somewhat different in the larger granules. These, when they are cut 

 through in the process of sectioning, show three fairly well-marked 

 zones. The outer of these is made up largely of radiating, mycelial 

 bodies of varying shapes, some appearing as hyphse, others as twisted 

 and bent mycelia, and in some sections a more or less definite "club" 

 formation may be noted: The middle zone is composed of irregularly 

 interwoven mycelia Avith a few irregular forms, a mass of poorly stain- 

 ing material, degenerated cells, and a few crystals is embedded in it. The 

 third or inner zone seems to resemble a cavity filled with granular and 

 hyaline matter, broken-down cells and irregular forms of the Strepto- 

 thrix; these latter being of several shapes, of which the bacillary and 

 coccus-like predominate. (PL 3, fig. 1.) 



THE STREPTOTHRIX. 



Morphology. — A Streptothrix answering to the following description 

 was found in large numbers in the discharges from the open sinuses 

 and the various tissues of the diseased foot after amputation; it was 

 cultivated and the disease was produced in monkeys' feet by inoculation 

 with cultures and scrapings from the amputated member. 



The discharges and scrapings from the cut surfaces of the foot, on 

 microscopic examination, show the distribution of the Streptothrix 

 to be very general and not confined to any particular tissue, or even to 

 the sinuses and cavities. The organism is easily recognizable in fresh 



