560 Wisconsin Academy of Sciences, Arts, and Letters. 
area. The study of the fresh material was not carried further 
and the internal organs, already in a state of decomposition, 
were not examined. 
Portions of the diseased tissue were fixed in Schaudinn^s alco¬ 
hol-sublimate mixture and in Fleming’s stronger fluid. The sec¬ 
tions were cut in paraffin 5 to lOfi in thickness and stained with 
Heidenhain’s iron haematoxylin and Delafield’s haematoxylin. 
The cyst envelope already mentioned in the description of the 
fresh material stains deeply with the haematoxylin (Plate IY» 
Fig. 2). Two kinds of cysts can be distinguished in the prepara¬ 
tions. Firstly, there are cysts containing a single largfe nucleus. 
The cytoplasm of these cysts shows a coarse net-work containing 
faintly staining granules. There also occur in the cytoplasm 
deeply staining chromidial masses (Plate IV, Fig. 2). These chro- 
midial masses resemble both in their occurrence and structure 
very closely the masses described by Awerinzew (:09 p. 343) in 
Lymphocystis johnstonei. In each of the cysts containing chromi¬ 
dial masses there is a single large nucleus irregularly spherical in 
shape and of a diameter approximately one third that of the 
cyst. We are unable to decide whether the irregular form of 
the nucleus is natural or due to poor fixation but are inclined to 
the latter view since in the preparations also the cyst envelopes, 
which in the fresh state are regularlly spherical, appear irregular 
and shrunken. Secondly, there are cysts containing amoebulae. 
In these cysts no large nucleus is found. The cytoplasm stains 
more deeply and the chromidial network described above seems 
to have completely filled the cyst. Distributed in this network 
are to be found unstained areas containing a faint and fine mesh- 
work in the centre of which is a deeply staining body. These 
are undoubtedly to be recognized as the amoebulae of Awerinzew 
(:09, p. 356). The central body is the nucleus. 
The close resemblance between the parasite described and 
Lymphocystis johnstonei Woodcock as described by Awerinzew 
(:09) would seem sufficient reason for assigning it to the genus 
Lymphocystis. 
Although the genus Lymphocystis is certainly to be included 
in the Sporozoa its more precise systematic position is a doubt¬ 
ful question toward the solution of which we are unable to con¬ 
tribute. 
