1912.] 



A Note on the Protozoa from Sick Soils. 



399 



In addition to these monads I have succeeded in obtaining pure animal 

 cultures of a number of other forms. Amongst these some have been 

 previously described by other workers, and I give a short list of the forms 

 that I have up to the present identified : — 



(1) Chlamydophrys stercorea ; (2) Amceba diploidea ; (3) Amoeba sp.? 

 (4) Amceba sp. ? (5) Amoeba sp. ? (6) Copromonas ; (7) Bodo sp. ? 

 (8) Prowazekia sp. 1 (9) Astasia sp. 1 



To some of these forms I hope to return in my later paper, but I should 

 like to point out that I have now worked for over a year with cultures of a 

 form which seems to me absolutely identical with Chlamydophrys stercorea, 

 and have entirely failed to find any indication in confirmation of Schaudinn's 

 account of the sexual stages of this form. This is the more difficult to 

 understand as the account and the figures which he has published of the 

 asexual stages are in complete accord with those I find in my cultures. 

 Schaudinn, as will be remembered, stated* that in all his cultures, at the 

 end of a few days, a formation of flagellate gametes set in, which after an 

 isogamous conjugation gave rise to small zygote-cysts. These cysts, according 

 to his account, could only be further cultured after the passage through the 

 gut of some vertebrate. My cultures, under a large number of different 

 conditions, have uniformly ended in a cyst formation without any sexual 

 process, and these cysts could always be readily cultured on all fresh media, 

 and would not pass in a living condition through the gut of a fowl. I have 

 found flagellates in some of my early Chlamydophrys-cultmes, but I hope 

 to be able to show in my forthcoming paper that these are parasites, and 

 have no connection with the life-cycle of Chlamydophrys. 



EXPLANATION OF PLATE. 



All the figures were drawn with a camera lucida under Zeiss comp. oc. 18 and 

 1*5 apochr. objective. 



All the figures except 1, 2, 11, and 12 were drawn at table level. 



1. Normal round form of Monas termo. 



2. Active elongate form. 



3. Early stage of division ; the flagella and blepharoplasts have divided. 



4. Slightly later stage of division ; the blepharoplasts with their attached flagella are 



beginning to separate, and the nucleus is filled with a number of spherical 

 masses of chromatin. 



5. The blepharoplasts with their attached flagella have moved apart so that the 



enlarged nucleus filled with the chromatin-spheres lies between them. The 

 blepharoplasts are still united by a thread which stains faintly with eosin. 



* " Untersuchungen fiber die Fortpflanzung einiger Ehizopoden," 'Arb. a. d. kais. 

 Gesundheitsamt,' 1903, vol. 19, p. 547. 



