SEAT OF PRIMARY INVASION. 221 



which the disease extends. In the periphery of the primary lesion 

 he found numerous nodules which later became the seat of destruc- 

 tive changes, resembling in this respect the clinical features of tuber- 

 culosis of the skin. The extension of the disease in the direction 

 of the deep tissues takes place by the formation of passages the cir- 

 cumference of which corresponds to the size of a lead-pencil ; these 

 are filled with yellowish-gray or reddish-gray granulations which 

 attack and destroy tissues irrespective of their anatomical structure. 

 The lymphatic glands were always found intact. 



2. Alimentary canal. The frequency with which the disease 

 aifects the mouth and jaws of cattle is explained by the occurrence 

 of numerous points of injury caused by the chewing of rough food, 

 which furnish the necessary infection-atrium through which the 

 fungus enters the tissues. 



a. Teeth. In man infection takes place frequently through 

 carious teeth and through abrasions in the tongue and mucous 

 membrane of the mouth. 



Israel (Klinische Beitrage zur Kenntniss der Aldinomykose des 

 Menschen, Berlin, 1885) found the fungus in the cavities of carious 

 teeth, and Partsch found, in the same locality, almost pure cultures 

 without any manifestations of disease except chronic periodontitis. 

 The fungus occurs here often side by side with leptothrix. 



b. Tongue. Hochenegg saw a case of actinomycosis of the 

 tongue caused by an infected carious tooth. The swelling was the 

 size of a cherry located near the apex of the organ. The aifectiou 

 had existed for two months. The growth was excised, and on 

 examination was found to consist of granulation tissue with a 

 central yellow mass the size of a millet-seed. Beside this case 

 only three cases of actinomycosis of the tongue are on record ; one 

 primary, one secondary to disease of the jaw, and one metastatic. 



c. Jaws. That carious teeth furnish a frequent infection-atrium 

 in maxillary actinomycosis is well known, and in many instances 

 the disease in its early stages has been mistaken for an ordinary 

 dental affection, and patients have often sought relief at the hands 

 of a dentist. The lower jaw is most frequently affected, the 

 growth being connected with the bone, or situated close to it, or it 

 has already extended to the submental orsubmaxillary region. As 

 soon as the loose tissues of the neck are reached, rapid extension 

 takes place in a downward direction along the inter-muscular septa. 

 Israel refers to a case in which an actinomycotic swelling in the 

 submaxillary region extended, from the month of August to 

 December, to the level of the thyroid cartilage. When the disease 

 is primarily located in the upper jaw, which, however, occurs only 

 in exceptional cases, it tends to invade rapidly the adjacent soft 

 parts, and even to implicate the base of the skull and the brain. 



