ENDOLIMAX NANA I03 



Werner (191 2) apparently observed the cysts of E. nana but con- 

 sidered them to belong to E. coll. At all events, his crude figures (PI. II, 

 figs. 19, 20, 23, 29, 30) are far more like cysts of £, nana than those of 

 E. coli, to which they are attributed. 



E. nana was described as a separate species by Swellengrebel and 

 Mangkoe Winoto (1917) under the peculiar name " limax" : and later in 

 the same year Kuenen and Swellengrebel (1917) described apparently the 

 same form again, naming it Endolimax iiitestinalis. Brug (1917) pointed 

 out that the organism described as Entamoeba nana by Wenyon and 

 O'Connor (1917) could hardly be placed in the genus Entamoeba — as 

 was, indeed, obvious : but his proposal to place it in the genus 

 Vahlkanipfia instead — as Vahlkampfia nana — was even more open to 

 objection. No matter what interpretation is put upon this genus — and in 

 my opinion the name Valilkampfia should not be used for any organism 

 —it is clear that E. nana has nothing whatever to do with any of the 

 free-living amoebae for which it was intended. On the appearance of 

 Kuenen and Swellengrebel's (19 17) work, Brug (1918) corrected his 

 earher opinion ; and as the work of Wenyon and O'Connor appeared 

 before that of Kuenen and Swellengrebel, he pointed out that the specific 

 name {nana) proposed by the former must stand, though the generic name 

 {Endolimax) of the latter should be used instead of Entamoeba for the 

 organism in question. Its correct name would thus be Endolimax nana. 



This organism can hardly be placed in the genus Entamoeba, on 

 account of the peculiarities of its nuclear structure and its cysts. On the 

 other hand, there was — prior to the introduction of the name Endolimax 

 — apparently no genus to receive it. Although I regard this generic 

 name as inappropriate, in that it implies * a resemblance of this form to 

 '* Amoeba Umax," I believe Drug's amendment must be accepted, as it is 

 in accordance with the rules of nomenclature. 



I would here call attention, however, to the apparent similarity of 

 E. nana to a curious organism discovered by Minchin (1910) in the 

 malpighian tubules of fleas (Ceratophyllns fasciatns), and named by him 

 Malpighiella refringens. The systematic position of this parasite is still 

 uncertain, though it is described as " amoeboid " : and it forms 4-nucleatc 

 cysts with a structure apparently very closely similar to those of E. nana. 

 Similar organisms have since been recorded by Alexeieff (1913) from the 

 vagina of a leech (Hirndo niediciiialis), and by Noller (1914) from dog- 

 fleas and rat-fleas. Neither of these authors, however, has ascertained 

 definitely whether Malpighiella is an amoeba or not. The former thinks 

 it is, the latter that it is not. If it really is an amoeba, then it seems not 

 improbable that E. nana may have to be placed eventually in the genus 

 Malpighiella, from which it seems at present to differ in no characters of 

 generic magnitude. Unfortunately I have not yet been able to investigate 

 Malpighiella with a view to deciding this question. 



Attention may also be directed to an amoeba described from the 

 faeces of frogs by Epstein and Ilovaiski (1914), and named by them 

 Naegleria ranarnm. The organism is said to be " semi-parasitic," and it 

 certainly cannot be placed with propriety in the genus " Naegleria." The 

 cysts of this species appear to be very like those of E. nana in certain 



• This, at all events, appears to have been the authors' intention : though it may be 

 remarked that Limax is the name proper to a slug, and therefore Endolimax would be 

 a more suitable name for a parasitic mollusc than for a protozoon. 



