192 DB. HBNEAQE GIBBES. 



I next examined a number of kidneys from the human foetus 

 about full time. In every case where the kidney was fresh 

 and had been hardened in alcohol, I found the cilia in the con- 

 voluted tubes. They seemed to be much more widely dis- 

 tributed than in the adult animals I had previously examined. 

 They were to be seen in many more tubes in one field of the 

 microscope, and they were present in a large number of trans- 

 verse sections of convoluted tubes. It appeared, in fact, as if 

 they were present in all the convoluted tubes, proximal and 

 distal. They are very minute, and there are a large number on 

 each cell ; they require great care in the preparation to show 

 them well, and the sections must be very thin. I found log- 

 wood to be the best stain to bring them out. 



The kidney must be perfectly fresh. 



I examined a large number of adult human kidneys without 

 finding any cilia in the convoluted tubes. I attributed this to 

 the difficulty of obtaining them in a perfectly fresh state. I 

 found traces in some, but it was not until last year (1882) that 

 I succeeded in getting them out satisfactorily. 



A case of progressive pernicious anaemia was sent me for 

 examination, and on making specimens of the kidney after 

 hardening, I found that numbers of the convoluted tubes 

 contained cilia. 



They resembled those in the foetal human kidney, but were 

 not so widely distributed. They are shorter than those found 

 in the kidney of the mouse and rat, and they are very much 

 finer and more numerous than the cilia on the cells of the 

 human trachea. 



In the adult kidney they stained deeply at the base, giving 

 the appearance of a dark line at the free edge of the cell. 



They can be easily seen with a ^th objective, but the 

 binocular microscope, with either a ^th or |^th, brings them 

 out very plainly. 



Professor Tuttle, of Ohio, has observed cilia in human 

 kidneys from cases of smallpox, also in kittens. 



