102 THE AMEKICAN MONTHLY [May, 



mode of introduction into the system, and grovvtli, and the pathological 

 changes resnlting from its presence. 



If we take a part of the tumor we have mentioned or a piece of tissue 

 adjacent thereto, we find on examination small round bodies lying 

 either singly or in groups or clusters. 



One of these bodies we will proceed to examine with the microscope 

 and describe. Occupying the centre of the mass we find a thready fun- 

 gus, the filaments being similar to the ordinary mycelium. These 

 threads have a single bulb-like termination or may branch in various 

 directions, each branch being tipped with a similar enlargement at its 

 extremity. Some filaments present bead-like enlargements. 



These filaments appear to be attached to the centre of the growth, 

 from which they radiate, as shown in the complete fungus, giving the 

 entire mass the appearance which lias led to the name of actinomyces 

 or ray-fungus. 



Surrounding some of these masses of fungus, and in fact all the larger 

 and older ones, we find evidences of inflammation set up by the pres- 

 ence of this foreign body. We have a dense layer of granulation tissue 

 with some epithelioid cells and bands of fibrous tissue, but the giant 

 cells and capsule described by some observers I have not seen. In some 

 of the smallest deposits this appearance is wanting, the deposit being 

 seemingly a recent event, and the inflammatory pi-ocess not yet begun. 



From this last observation we are led to conclude (and this corre- 

 sponds to the facts observed in the history of recorded cases) that this fungus 

 causes inflammation and the deposit of granulation tissue, which mass 

 is prone to undergo degeneration, giving rise to suppuration in the 

 surrounding tissues, the small seed -like masses of the fungus being 

 found in the pus escaping from abscesses thus formed. These small 

 particles may be seen with the unaided eye and felt with the fingers, be- 

 ing of a yellowish color, about the size of millet seed, and of a cheesy 

 or greasy feel. 



The questions now arise. Where does this fungus come from, and 

 how does it gain admission into the system.'' Of the first it is sufficient 

 to say that the source of supply is not known. The fungus so far has 

 not been found outside the bodv of animals. It is proliable, however, 

 that it does exist attached to vegetable matter which is used for food by 

 man and herbivorous animals, as the carnivorous animals are said to be 

 exempt from its unfriendly visitations. From the fact that it usually 

 attacks the jaw and finds an entrance into the svstem tlirough abrasions 

 of the mouth, carious teeth or the extraction of teeth, it has been sup- 

 posed that when taken into the stomach the fimgus is destroyed by the 

 action of gastric juice, but if arrested in the buccal cavity and finding 

 an entrance to and lodgment in the teeth or jaw, it rapidlv grows and 

 spreads by burrowing into neighboring tissues or bv embolism to dis- 

 tant parts of the body. There are. however, cases which cannot be ac- 

 counted for in this way. Where the fungus has appeared as a primary 

 deposit in kidneys, lungs, and even the brain, in such cases it is sup- 

 posed that a minute particle of the fungus w'as taken into the lungs 

 during inspiration, and gaining an entrance into the blood was carried 

 to a distant organ, where it grew and developed, and caused the patho- 

 logical changes which brought about its discovery in these unusual lo- 

 cations. 



