5o0 
Entamoeba gingivalis 
the contrary, namely, that if precautions are taken to avoid contamina¬ 
tion with the superficial debris, material collected from deep pockets is 
less rich in amoebae than that collected from a more superhcial area. 
9. Male, aged 34, with mouth in a very unhygienic condition. The 
buccal and labial surfaces of the teeth were badly discoloured, some of 
the posterior teeth being coated with salivary tartar, whilst all the 
remaining molar and premolar teeth had a rim of hard calculus at the 
cervical margin on both the buccal and lingual surfaces. There was 
a marginal gingivitis in both jaws, but no suppuration could be detected 
except around the left mandibular second molar, where it was very 
slight. The interdental papillae were reduced in size and inflamed. 
There were no distinct pockets, but in places the alveolar border and 
gum had shrunk, leaving the neck or the root of the tooth exposed. 
The amoeba was found on both the salivary calculus and the rim 
of hard dark calculus at the gum margins; amongst the white deposit 
on the buccal surfaces of the molars, and in the debris beneath the 
inflamed gum margins. 
10. Male, aged 37, emaciated, thin and anaemic, suffering from 
chronic rheumatism. He was sent from a General Hospital for dental 
treatment. His mouth was in a very neglected state, with several 
badly broken-down septic roots, the buccal surfaces of the remaining 
posterior teeth covered with salivary calculus, and the usual rim of 
hard dark tartar associated with marginal gingivitis at the necks of the 
anterior teeth, and on the lingual aspect of the necks of the posterior teeth. 
The marginal gingivitis was very pronounced. Hanging-drop prepara¬ 
tions and stained films from both kinds of calculus, and from the matter 
expressed from the gum margins showed abundant active amoebae. 
11. Female, aged 40. Recession of gum around buccal roots of 
left maxillary first molar. No pus present, and no pockets. Films 
made from debris on the exposed roots showed amoebae. 
12. Female, aged 38. Recession of gum from buccal and distal 
surfaces of left upper maxillary second molar due to presence of calculus, 
but there was no visible suppuration. Stained films showed the pre¬ 
sence of amoebae. 
13. Male, aged 43. Pyorrhoea affecting all remaining maxillary 
teeth including the incisors, canines and second molars. There was 
recession of the gums all round the teeth and the formation of pockets 
on the lingual aspects of the incisors and canines and the mesial sur¬ 
faces of the molars. The whole of the palatal surface of the gums, 
periosteum, and that between the canines and second molars was in a 
