268 The Philippine Journal of Science 192s 



within the cells themselves, especially those showing necrosis or 

 advanced degeneration. No definite evidence of phagocytosis of 

 the organisms by leucocytes has been observed, but in those 

 miliary abscesses which appear oldest, as indicated by leu- 

 cocytic disintegration and more superficial situation, the organ- 

 isms are much less abundant than in the newly forming ones 

 which lie deeper in the epidermis. From this it is inferred that 

 the treponemata disintegrate and disappear gradually in the 

 presence of abundant polymorphonuclear leucocytes. 



While the epidermis is undoubtedly the most favorable site 

 for the growth of these organisms they are not in this lesion 

 entirely confined to the epithelial layer, but occur in great num- 

 bers in oedematous perivascular connective tissue in certain of 

 the long papillae which extend far up into the thickened epi- 

 dermis. They are present only in the terminal portions, and 

 in only a few papillae. 



Yaw 2. — October 10. Forty hours after the injection of 0.3 

 gram of neosalvarsan intravenously the lesions are pinkish in- 

 stead of yellow and purulent, less elevated, and much improved. 

 Yaw 2, measuring 0.7 centimeter in diameter, was removed by 

 Doctor Franco. 



Even in so short a period there is marked change in the histo- 

 logical picture, especially of the epidermis. On the surface is a 

 thin layer of leucocytes and desquamated epithelial cells some- 

 times communicate with the remnant of a miliary abscess deeper 

 down; but miliary abscesses and foci of dense cellular infiltra- 

 tion are rare within the epithelial layer. There are still great 

 numbers of leucocytes irregularly scattered throughout the epi- 

 thelial layer, lying in intercellular spaces and sometimes ag- 

 gregated in small nests, but the great mass of them have been 

 cast off onto the surface or removed in other ways. The thick- 

 ened and elongated epithelial columns are much more compact 

 than in the previous section, due largely to the loss of intercel- 

 lular exudate. 



The papillae extending upward into the thickened epidermal 

 layer are still greatly swollen by serous, fibrinous, and cellular 

 exudate and by dilated blood vessels and capillaries. Polymor- 

 phonuclear cells appear to be more numerous in the perivascular 

 exudate than before treatment, but their condition's are es- 

 sentially altered. Many are being engulfed in great numbers 

 by the phagocytic activity of large mononuclear leucocytes, 

 which appear now to be the most active component of the lesions ; 

 others are necrotic. 



