NOTES AND MEMOKANDA. 277 



of the stigmata, is so considerable, that the sheath of the vessel, at the 

 correspoucling spot, stands out like a little hump from the epithelial 

 layer. From this the author concludes that the white blood-corpuscles 

 in inflammation pass through the wall at the cement substance, i. e, 

 the stigmata ; whilst, on the contrary, he never saw that other parts 

 of the wall of the vessel, e. g. the epithelium, was permeable to the 

 white blood-corpuscles. From experiments made with gelatine and 

 fine vermilion injections, it seems that, in addition to the pronounced 

 wandering out of colourless blood-corpuscles connected with disturb- 

 ances in the circulation, other corpuscles also pass through the wall 

 of the vessel ; and apparently this also happens at the portion of the 

 stigmata and cement substance. When blue-coloured gelatine instead 

 of the vermilion was employed, the inflamed vessels at numerous 

 spots here seemed to be covered with small roundish blue protube- 

 rances, or with more elongated blue processes. From this it results 

 that the wall of the vessel permits not only substances in solution 

 to pass through it at the position of the stigmata and cement substance, 

 but also a colloid body (gelatine) and other elements (vermilion). 

 The masses which have passed through the vascular walls, penetrate in 

 the direction of the "juice canals " (" Saftcanalsystem ") in the tissue, and 

 under certain circumstances these can be completely filled laterally 

 with the injection mass. Still the configuration of this system of 

 spaces when injected is variable, according to the disturbances of the 

 circulation which have occurred in the tissues. Whilst the jiuce- 

 canals during venous stasis possess a broad and ampullated form, they 

 appear smaller, and more zigzag in those disturbances of the circu- 

 lation which are specially characterized by the exit of white blood- 

 corpuscles. 



NOTES AND MEMOKANDA. 



A New Form of the Phylloxera. — M. Balbiani, the distinguished 

 entomologist, has adtlressed to M. Dumas a letter on the egg of the 

 phylloxera, from which the following passages are gleaned as being 

 of importance : — " I have to inform you that on examining, this 

 morning, April 9, through the magnifying glass, a certain quantity 

 of winter eggs I had collected a few days ago (there were some 

 twenty of them on the same bit of vine shoot, 19 centimeters long), 

 my attention was suddenly attracted to a yellow point there was 

 among these eggs. It turned out to be a young phylloxera just 

 hatched, for the little parasite still carried the egg-shell about with 

 him. For more than two hours it remained perfectly motionless, 

 but all its appendages, feet and antennae, were entirely spread out and 

 well visible. At length it began to move, and soon grew rather 

 lively on the lamella of bark on which it stood. By microscopic 

 inspection I acquired the conviction that the ofispring of yesterday's 

 egg, which, according to all analogy, represents the fundamental 

 progenitor of the subterranean colonies, really constitutes a fourth 



