180 



FAMILY: AMCEBID^E 



Hwmatococcus. It is possible that both these forms, as well as the others 

 named above, should be included in the genus Vahlkampfia. 



These various amreba? all agree with one another in that the nuclear 

 division, where it has been studied, is of the type first described by 

 Vahlkampf (1905), and it is highly probable that further investigations 

 will demonstrate, in some of them at least, the presence of pores in the 

 cyst wall and the occurrence of flagellate stages, in which case they wall 

 have to be transferred to the genus Diynastigamoeha. Meanwhile, however, 

 till more accurate data are forthcoming, it seems advisable to group these 

 amoebae under the name Vahlkampfia, which, as pointed out above, may 

 be a synonym of Dimastigamoeba, rather than to establish a new genus, 

 which will be necessary if they are finally proved to have no flagellate 

 stage. 



Oeniis : Sappinia Dangeard, 189(5. 



The amo'ba? belonging to this genus are peculiar in possessing two 

 nuclei, which are closely applied to one another. During division, both 



Fig. 91. — Sax^pinia diploidea ( x 2,000). (After Dobelt. and O'Connor, 1921.) 



1. Ordinary individual with two nuclei in apposition. 



2. Cyst containing two individuals. 



nuclei divide. When encystment takes place, two amoebae, each with 

 two nuclei, are enclosed in a common cyst. In the form S. pedata, studied 

 by Dangeard (1896 a), the free amoebae have the characteristic two nuclei. 

 The cyst, however, is peculiar in having a pedicle or stalk attaching it to 

 objects. 



Sappinia diploidea (Hartmann and Niigler, 1908). — This is an amoeba 

 which was isolated by Hartmann and Niigler from lizards' faeces. Accord- 

 ing to Dobell and O'Connor (1921), it occurs rarely in human faeces, but more 



