438 



to coutiiin 7 nuclei. 3 vesicular and 4 solid, suggesting that the number 

 may not be constant. This would correspond with what occurs in other 

 genera e. g., chloromyxum. according to Joseph\ in which the number 

 of nuclei in the sporoblast seems to vary. 



Of the 6 nuclei of the sporoblast 2 go to form the valves of the 

 sheath, 2 attach themselves to the polai* capsules, and 2 remain in the 

 protoplasm of the spore ^amoboidkeim (Fig. ll"i. This is the same 

 arrangement as is described by Schröder in SpJiacronn/.ia. The two 

 last-mentioned nuclei may fuse into one Fig. 12 c\ In the protoplasm 

 of the spore two large vacuoles are often seen one near to each polar 

 capsule ^Fig. 12a\ The spore-coat, as noted by Mackie, is ribbed or 

 striated: the striations are best seen in some spores which have been 

 divided transversely in cutting the section ;Fig. 13 . 



According to my own measurements the spores average 16 // in 

 length by 5 u in breadth. A few measure as much as 1~ u. Examples 



Fio-. 12. 



Fio-. 11. 



Fiof. 13. 



a. b c. ^) 



Fi^. 11. Sporoblasts. showing nuclei aud formation of polar capsules. 



Fig. 12. Spores of Mi/xi'lium machi'ci. a . showing vacuoles and remains of one 



caps\üar nucleus; b. vesicular nuclei in protoplasm and attached to polar capsules; 



c. single central nucleus in rounded mass of protoplasm A™ö boidkeim". 



broader than ö u are not uncommon, and seem to represent immature 

 spores, as the sporoblast elongates and becomes thinner in the process 

 of development Figs. 11 and 12(-\ 



The only species of myxidiiuu previously recorded as existing in a 

 chelonian host is J/, danileuskyi, described by I. a ver an in the kidney 

 of Emi/s orbicularis (L.i [Cisfudo europoea, in which the spores measure 

 12 u in length. If, as it would seem, the present species has not been 

 previously described. I would venture to suggest for it the name of 

 Miixidiuiu macl-iei. after the name of its discoverer. 



Keferences. 



Schröder. 1907. Arch. f. Protistenk.. IX. 359. 



Joseph. 1907. Arch. f. Protistenk. YIU. 398. 



La ver an, 1897. C. R. Soc. de Biolosrie. Julv 17: and 1898. Jan. 8. 



