512 EDEMA FOLLOWING NEPHRECTOMY 



Removal of Portion of Wolffian Ducts. 



A series of 62 larvae was operated upon; the nature of the experi- 

 ment varied from that just described in that, instead of extirpating 

 the glandular portion of the pronephros, sections of its duct, on either 

 side, were cut out just cephalad to the cloacal opening. Larvee of 7 

 mm. in length were used in this experiment. 



20 hours after the operation, examination of the larvae showed 

 great swelling of the glandular part of the pronephros. The swell- 

 ing protruded as large knots of edematous tissue on either side of 

 the head region. Edema appeared in most of the larvae a few hours 

 later. A curious condition now resulted. In addition to the marked 

 turgor of the head region, and to the two swellings on either side of 

 the body, representing the hyper trophied pronephros, there was a 

 large edematous swelling on either side of the larva in the posterior 

 part of the body at the place where the cut ends of the Wolffian 

 ducts ended bhndly in the tissues. Evidently the pronephros was 

 functioning, but the fluid was being forced into the tissues of the 

 posterior end of the body. 



An operation of a somewhat different nature from those recorded 

 above was also attempted. Twenty-five larvae, measuring 7 mm. in 

 length, were used. The Wolffian ducts on either side were severed, 

 just cephalad to the cloacal opening, and dissected out anteriorly 

 well up toward the glandular portion of the pronephros. The ducts 

 were permitted to hang outside the larvae through the incision made 

 in the body wall. Considerable mortality resulted, no doubt due to the 

 severity of the operation and consequent destruction of such impor- 

 tant vascular organs as the posterior cardinals and dorsal aorta. Two- 

 thirds of the larvae died during the first 24 hours, and at the end of 36 

 hours only three remained alive. When examined, they showed prac- 

 tically no edema, except a slight turgor of the head lymph sinuses 

 and swelling of the glandular portion of the kidney. The Wolffian 

 ducts still hung outside the body and were apparently function- 

 ing as excretory ducts, despite their abnormal position. The in- 

 cision in the body wall at the point where the ducts protruded had not 

 healed at this time. Complete healing of the wound would no doubt 

 have pinched off the ducts or else have closed them by pressure. All 



