SOIL PROTOZOA. 3 25 



produced in the endoplasm is, but tliey ai'e of fairly commou 

 occurrence in the cysts of other forms of Umax amcebae. At all 

 events they are not particles of chromatin extruded from the 

 karyosome, for this does not diminish in bulk to any great 

 extent, and, moreover, there is a suificient volume of gianular 

 material produced in the endoplasm to make several karyosomes 

 if it were fused together. Probably they are of a reserve food 

 character. I cannot, however, throw any light on their presence 

 or absence in newdy excysted organisms, for I did not make any 

 observations on the excystation of this amoeba. 



(d) Remarks. 



Dobell has gone very thoroughly into the differences and 

 similarities between his AiiKjeha glehce and its nearly related 

 forms, so that it is quite unnecessary for me to go into this 

 question in detail. I will merely point out, therefore, in what 

 respects my organism differs from or resembles A mceba glehce. 



It is obvious, from a comparison of the figures illusti^ting this 

 account and that of Dobell, that the amcebae to which they refer 

 are very closely related in their method of nuclear division. 

 The type of division is the same in each, and it is merely in 

 details that differences are presented. The most impoi-tant are 

 the following: — 



1. Amceba lawesiana is a somewhat smaller organism than 



Amoiba gleha;. 



2. The nuclear membrane persists to a much later stage of 



division in Amosba lawesiana than in Amoeba glehce. 



3. The spindle formed in the division of the nucleus is 



sharply pointed at each end in Amoeba knvesiana smd 

 is rounded or barrel-shaped in Amoeba glehce. 



4. The resting-cyst of Amoeba lawesiana is iriegular in out- 



line, whei'eas that of Amceba glehce is perfectly round 

 and has a smooth outer wall. 



5. Within the endoplasm of the cyst of Amoeba Icctvesictncc 



large numbers of deeply staining granules are produced, 

 whereas in the cyst of A7noeba glehce highly refractive 

 granules occur. 



(2) Am(eba agricola, sp. n. (PL IV. figs. 66-74.) 



I pi'opose to describe under this specific name a small amoeba 

 which occurred in one of the cultures made from Hoosfield 1868 

 soil. It exhibits some rather remarkable appearances during 

 the division of the nucleus, which seem to differ from any of the 

 already described nuclear divisions in amoebae ; and it is on the 

 strength of this fact that I propose the creation of a new species 

 for its reception. I made no special observations on the live 

 animals, so that, in this respect, what I have to say about them 

 is, unfortunately, incomplete. My notes merely record the 

 presence of numerous Ihnax amcebce in this particular culture, 



Proc. Zool. Soc— 1916, No. XXII. 22 



