Mavor — Strasser—On a New Myxosporidian. 679 
gative cells (Keysselitz, 1908) contain a single nucleus en¬ 
closed in a well defined mass of protoplasm (Fig. 2, a). The 
division of the nuclei of these ells has not been observed but 
cells containing a large and a small nucleus are abundant 
(Fig. 2, b). Ceds containing two large and two small nuclei 
are also to be found and identified as the beginning of the 
pansporoblasts (Fig. 2, c, d). Whether such cells arise from 
the union of two binucleated cells as described for Myxobolus 
Fig. 3.—Stages in the sporogenesis of Henneguya wisconsinensis: a and b, 
pansporoblasts; c and rf, spores; a and d from fresh preparations, b and c from a 
preparation stained with Delafield’s haematoxylin. a, X 1100, b — d, X 4000. 
pfeifferi by Keysselitz (1908) we are not able to say. The 
occurrence of stages containing three nuclei makes this 
doubtful (Fig. 2, e, /). Later stages in the development of 
the pansporoblasts (Fig. 3, a and b) show that two sporo- 
blasts are developed in each pansporoblast. The fully de¬ 
veloped spores show two nuclei in the sporoplasm. 
