226 LEECHES 



There have also been observed numerous small circular 

 bodies of inconstant size. The}^ have been seen lying freely 

 in the meshes of the mycelium and also closely applied to the 

 filaments. These bodies are not spherical, but thin and flat- 

 tened, and some of them present a curved appearance, convex 

 on the outer side and concave on the inner side. They sug- 

 gest the possibility of having been closely applied to the fila- 

 ments and have something of a scale-like arrangement. With 

 possibly one exception, no trace of blood vessels has been 

 found in the nodules. 



In the circumnodular tissue pathologic conditions exist 

 consisting of certain areas of tissue necrosis. 



There is an infiltration of the connective tissue with a 

 great number of wandering cells. In some places there are 

 well-defined nests in the stroma of the connective tissue, 

 simulating, perhaps, a cancerous appearance. The character 

 of the cells, which present a curiously vacuolated condition, 

 would, however, tend to eliminate this view. The vacuoles 

 vary in number and size, the average number being lo to 12 

 in a cell. 



In some preparations numerous leucocj'tes, of the mono- 

 nuclear and poly nuclear variety, had drifted away from the 

 nodule. They were for the most part elongated, and in all 

 the nucleus or nuclei appeared to be in a healthy condition. 

 The cells contained numerous small bodies, which took a deep 

 orange color with the Biondi-Ehrlich stain. In places adjacent 

 to these leucocytes there were frequently noticed a number of 

 these small bodies apparently lying free in the tissue. No 

 definite cell wall was distinguishable in the leucocytes. 



The vacuolated cells are present in greater numbers than 

 the heavily laden leucocytes. In the lormer nuclei were 

 present and presented various phases of change. In some 

 there is a single nucleus, which may be circular, crescentic, 

 or in the form of a dumb-bell ; in others there may be two or 

 more nuclei which in advanced cases appear only as remnants. 

 In extreme cases no nuclei at all are visible. The wall of the 

 wandering cell differs from that of the leucocytes proper in 

 possessing an appreciable thickness. This thickened boundary 



