lODAMOEBA BUTSCHLII III 



In the same publication Werner (191 2) figures three structures which he 

 calls " uninucleate cysts of E. coli with vacuoles" (see his figs. 16, ij, 

 22) : and these also appear to me to have been drawn from the present 

 species. But the figures are extremely bad, and at all events quite unlike 

 the cysts of E. coli. 



It seems to me possible that the "free-living amoebae" which 



Chatton and Lalung-Bonnaire (191 2) found in the human intestine, and 



•dentified as Vahlkainpfia punctata Dangeard, were really /. biitschlii. 



Vs noted already — in considering E. nana — it is highly probable that 



hey were not " V. punctata," which these workers cultivated from the 



;ame stool. Their description of the intestinal forms is too meagre, 



However, for me to identify them with certainty ; but to judge from the 



figures they were certainly not unlike the form under consideration. The 



same remarks are applicable to some of the " free-living amoebae from 



the human intestinal tract" noticed by James (1914) in Panama. His- 



igures 114-116 are certainly suggestive of /. bi'itschlii rather than E.nana, 



which species the rest of his " limax " amoebae should probably be 



ef erred. 



Wenyon (1915 a) briefly described and figured some "spherical 

 oodies," containing an " iodophilic" inclusion, found in human faeces. 

 Somewhat later (Wenyon, 1916) he redescribed them under the name of 

 " Iodine cysts" or " I. cysts." A fuller account, with some further facts 

 concerning them, was published by Wenyon and O'Connor (1917), who 

 gave them the same name. Wenyon (1915 a) regarded these bodies as 

 " probably of a vegetable* nature," and stated later (1916) that this " is 

 proved by the fact that they germinate when kept in faeces." Dr. 

 Wenyon called my attention to these bodies in 1915, and since then 

 I have studied them in stools from many different persons. At first I 

 agreed with him that they were probably vegetable organisms, but I now 

 know that they are really the cysts of the amoeba described in this 

 section. They have become familiar — since Wenyon's account — to 

 most workers in England under the name of " I. cysts," or " I. bodies." 

 Brug (1917), in Java, redescribed them as " Joodcysten," and regarded 

 them as probably " a new sort of parasite " altogether — what sort, he 

 did not suggest. 



Later, Kuenen and Swellengrebel (1917) found both the "I. cysts" 

 and the amoebae which form them in a single case, and provisionally 

 named the organism " Pseudolimax " — a name which they fortunately 

 state to be not subject to the laws of nomenclature. They made no 

 reference to the work of others on the same form, and apparently regarded 

 it as a kind of " limax amoeba" — which it certainly is not. Brug (1918) 

 subsequently pointed out that their "pseudolimax" was the organism of 

 the "I. cyst." Another Dutch worker. Flu (1918), has since found the 

 " I. cysts " once more, and has concluded that they are degenerate 

 cysts of E. histolytica — or, as he terms it, " E. tetragena." This is 

 undoubtedly incorrect. 



I first saw the living amoebaef which form the " I. cysts," I believe, 



* Matthews (1918) also states that " they probably represent some stage in the life- 

 history of a vegetable organism." 



t I may say that all my own work on this organism has been done in entire 

 ignorance of the simultaneous investigations of the Dutch workers, whose papers I was 

 not acquainted with until my own work was completed. 



