454 
H. M. WOODCOCK AND G. LAPAGE. 
in a marked manner — do not appear to be altered at all. 
They do not swell up, burst, or undergo any other obvious 
change. An interesting fact, moreover, which we noticed 
was that, when such preparations were looked at again the 
next morning, there did not appear to be as many ovals 
showing the contracted protoplasm as there were soon after 
the preparations were made. It seemed to us as if the proto- 
plasm must have expanded again in some individuals, which 
could not, therefore, have been dead. 
Of one thing we are sure, namely, that Selenomastix 
does not undergo what the Grermans term ‘‘ Praparations- 
plasmolyse.'’^ This is evident from our figures, which give a 
fair assortment of the various appearances seen in the stained 
preparations. Lest it might be thought that the condition in 
which there are one or two deeply staining masses (regarded 
by us as chromatiuic) in the cell, represents such an artifact, 
we may point out, first, that there is do larger proportion of 
such individuals on “ dried ’’ Giemsa smears than occurs in 
properly wet-fixed films, made as soon after removal from 
the rumen as possible ; secondly, that every transition can be 
traced in the development of this phase where the chromatinic 
substance is compacted into few masses, through conditions 
where there are a varying number of smaller, but quite 
prominent granules ; and finally, if it were an artifact, the 
ovals with the first type of minute structure, closely com- 
parable to that of the crescents, might be expected also to 
show it, which is never the case. 
We have now, we think, considered exhaustively the 
possible directions in which to look for the origin and affinities 
of this remarkable parasite, so far as we have been able to do 
so from the facts we have learnt with regard to it up to the 
present. To sum up, it appears to be entirely unconnected 
with the Dinoflagellates ; it may possibly be derived from 
some large spirillum, or from an Ophidomonas- or Rhab- 
domonas-like form, although we are very doubtful upon the 
point. For our own part, we are inclined to hazard the 
suggestion that if there is such a thing as a Pro-Protozoan or 
