Microbic Diseases Individually Considered. 269 



fungus) occurs in the specific tumors in the form of 

 yellow or occasionally colorless grains; when the ma- 

 terial in which they are contained is spread out on a 

 glass slip the-smallest of these grains appears some- 

 what like grains of sand; the larger are formed hy 

 the union of primary granules and are of various 

 forms. These grains are most frequently cretaceous, 

 having a hard, stony consistence. In size they vary 

 from 0-1 millimeter to 1 millimeter, or more. 



They are composed of one or several colonies of a 

 fungus the elements of which are arranged in rays. 

 In each colony there may be distinguished : 



1st. A central zone, formed of very fine filaments 

 ramifying and intermingled in a close felted net-work. 

 The diameter of these filaments is uniform in all parts 

 of the central zone; in structure they consist of hol- 

 low cylinders, each, at intervals, containing a nucleus 

 which readily takes up coloring matters. (1) 



The size of this central part of the actinomyces 

 corresponds with that of the tuft or colony; small in 

 microscopic grains it is of much larger dimensions 

 in those tufts which have acquired a considerable 

 volume. 



2d. A peripheral zone, rendered conspicuous by the 

 radiating elements of which it is composed ; these 

 elements are pyriform with their large extremities 

 losins: themselves in the tissue which surrounds the 

 colony and even occasionally penetrating into the 

 adjacent cells, and their slender ends passing into the 



(1) Actinomycosis and its parasite. See Annates de medicine 

 veterinaire, 1890. 



