M. A. Sclmeider on Oplnyocystis Biitschlii. 311 



The spores of Ojjhryocystis ButschUi have the form of 

 navicellffi and would pretty closely resemble those of the 

 Monocystis of the earthworm if the proportion of the longi- 

 tudinal to the transverse diameter were not slightly different ; 

 in the present case it is on the average as four to three, or 

 about that. Certain spores are more dilated than others in 

 the equatorial zone, as will be seen on comparing the spores 

 of figs. 33, 34, and 38, In fig. 35 we see a spore rounded at 

 one of its extremities; this is an exception. 



The normal spores, at maturity, all contain a very distinct 

 remanent nucleus placed in the centre, and falciform corpuscles 

 marked by extremely fine lines. We can recognize without 

 the least doubt the existence of these sporozoites ; but it 

 would be impossible to count them correctly in the intact 

 spore. I have expelled by pressure the sporozoites from 

 some specimens, but they are carried in all directions by the 

 return of the water when the pressure ceases. I cannot give 

 the exact number. I have ascertained the existence of the 

 nucleus in those which I met with free. 



I do not know whether the little dwarf spores, two of which 

 are produced in certain cysts, are corpusculated or remain 

 clear. They are so rare that I have been iinable to elucidate 

 this point. 



To enable the reader to avoid referring so often to the scale, 

 I will here give the most constant dimensions among those 

 relating to the description of the Ophryocystis : — 



/*• 



Diameter of the splierical iudividuals with a 

 single nucleus, destined to conj ugate (such 



as fig. 22) 12-14 



Longer axis of a cyst 16-20 



Shorter axis of a cyst 13-14 



Longer axis of a normal spore 12-14 



Shorter axis of the same 7-8 



Diameter of the two primitive nuclei of a cyst 



(such as that of fig. 26) 3 



Diameter of the nuclei in a cyst with six nu- 

 clei (such as that of fig. 24) 1*5- 2 



Summary. 



I will rapidly recapitulate the facts ascertained and the 

 arguments which flow from them with regard to the affinities 

 of Ophryocystis Biitschlii with other Sporozoa and even with 

 some other Protozoa : — 



1. Amocbiforra stage, with a profusion of processes anl a 



