1917] 



Boeck: Mitosis in Giardia microti 



TABLE OF INFECTION 



Slides 



Condition of host prepared Colon 



Alive 8 



Dead several hours 7 



Dead several hours 17 



Dead several hours 



Dead 2 days 23 



Dead 2 days 7 



Dead several days 



Alive 62 



Alive 7 



Dead 1 day 5 



Dead 1% days 9 



Dead 1% days 13 



Alive 17 



Dead (time?) 



Alive 12 



Alive 36 Cysts 



Alive 22 Not examined 



Alive 6 Hexamitus 



Alive 12 Not examined 



Alive 16 Very few cysts 



Alive 2 



Alive 5 



Alive 8 Not examined 



It would seem from the data set forth in the table that these flagel- 

 lates are very resistant to the degenerative conditions in the tissues 

 of the host which ensue at the time of death. Of the twenty-three mice 

 examined, ten Avere dead ; of these, six still showed the intestinal flagel- 

 lates present. In two instances the parasites were still living in great 

 numbers, after the host had been dead two days. Giardia microti 

 seems to difl'er from Giardia muris in resistance, the latter remaining 

 alive for only a few hours, while the former lived for two days. 

 Because of this characteristic hardiness, it seems as if they should 

 thrive under cultural conditions. 



Attempts were made to obtain cultures by placing some of the 

 intestinal contents with normal salt solution in a cell slide sealed with 

 vaseline. The parasites lived for only a short time in the preparations. 



It will be noticed, from the table, that the duodenum seems to be 

 the natural habitat of these flagellates. In series 29 and 33 a few 

 were found just below the caecum, probably preparing for delayed 

 encystment, or were there through contamination, some forms having 

 remained on the forceps used in the making of previous smears from 

 the duodenum. In series 21, 25, and 29 cysts containing only one 



