628 W. S. PERRIN. 
seems possible that the residuary nuclei of the pansporoblast 
of Pleistophora periplanete represent reduction bodies, 
and that in the case of Thelohania miilleri (and possibly 
other Oligosporogenea) the extrusion of these reduction 
bodies takes place later on from the spore itself. It is 
perhaps somewhat premature to attempt any homologisations 
or explanation of the meaning of these residuary nuclei in 
the present undeveloped condition of this branch of Protozoan 
research, more particularly in view of the fact that im no 
single case has conjugation been recorded in the case of a 
Myxosporidian, and in no single case has the development of 
an adult trophozoite from the sporoplasm of a resting spore 
been traced. In view, however, of the rapidly increasing 
number of cases in which conjugation has been shown to 
take place among the Protozoa, e.g. Actinospherium, it 
seems very improbable that the Myxosporidia will prove to 
be an exception to what is being shown to be apparently the 
rule among even the most unspecialised forms of life. The 
presence of these residuary nuclei and Stempell’s observa- 
tions on the spore of Thelohania miilleri are certainly 
suggestive of a preparation for conjugation. 
Among the bacteria themselves, a class of organism which 
has been regarded till lately as in no case exhibiting a 
conjugatory process among its members, conjugation in a 
modified form has been shown to take place.t The existence 
of the above-mentioned gap in our knowledge of the Myxo- 
sporidian life-history, and the silence of all observers on the 
subject of conjugation among the Myxosporidia are pheno- 
mena probably not unconnected with each other. 
Nore on A HITHERTO UNDESCRIBED PARASITE (?) OF 
PERIPLANETA ORIENTALIS. 
In the course of these present researches certain peculiar 
structures, which occurred in many of the stained prepara- 
' Schaudinn has recently (1902) shown that a kind of conjugation occurs in 
Bacillus bitschlii parasitic in the ileum of Periplaneta americana, 
