464 LEFEBVEE. 



I employed Borrel's fixative, the formula of which is given below, for the 

 small pieces of tissue taken either from the living or dead body: 2 



Grams. 

 Water 350 



Osmic acid 2 



Chromic acid 3 



Platinum chloride 2 



Glacial acetic acid 20 



However, I prefer Meyer's acetic acid sublimate solution which consists of a 

 saturated solution of bichloride of mercury, 100 cubic centimeters, and acetic acid, 

 0.5 cubic centimeter. This solution fixes well and interferes less with the 

 staining of the sections. 



The sections were for the most part either stained by the Ziehl-Neelsen method, 

 or with eosin and crystal violet and Gram's iodine solution. This second 

 process is the best for the study of the bacilli. 3 



I. 



The first important question to decide was what percentage of both 

 leprous and healthy individuals in Manila harbored Demodex. A 

 research of this character among healthy people has been attempted else- 

 where by several investigators. I have not had the means of doing so 

 under favorable conditions in Manila. I might have tried, it is time, in 

 a hospital, but the results would not have been above criticism, for all 

 parasitologists know the great influence of the morbid state on the 

 number of organisms living even in organs untouched by disease; and 

 in the case in question it is particularly necessary to keep in mind that 

 lymphatic, scrofulous, arthritic and many other affections also modify 

 the quantity of the sebaceous matter, in which Demodex folliculorum 

 lives. 4 



The results regarding the prevalence of Demodex published by different authors 

 vary exceedingly. Gruby 5 says he found Demodex folliculorum in the sebaceous 

 glands of 40 among 60 persons he examined. Moniez, and also Kaillet, considers 

 this a greatly exaggerated number. Megnin, 7 according to researches made on a 

 regiment of artillery composed of men from all parts of France, gives an average 

 of 1 out of every 10 individuals having Demodex. Borrel' examined 20 individuals 

 of different ages between 20 and 70 years and estimated the average at 50 per 

 cent; it is to be noted that the subjects of this last research were hospital patients. 

 Borrel also examined a large number of cases of epithelioma and found the 

 percentage infected to be increased. I shall refer below to his researches on 

 lepers. 



2 Aeariens et Cancers. Ann. Inst. Past. (1909), 23, 100. 



3 Baumgarten's process, recommended for differentiating the bacillus of Hansen 

 from that of Koch, sometimes gives misleading results. I have found, as several 

 observers have already noticed, that tubercle-bacilli as well as the bacilli of 

 leprosy are often stained by this process. 



1 Berlioz. Man. prat, des maladies de la peau. 3 ed. (1894), 160. 



Compt. rend. Acad. 8c. Paris (1845), 20, 569. 



'Zool. Med. (1895), 635. 



7 Parasites et maladies parasitaires (1880), 272. 



