The Presiclenfs Address. By the Rev. W. H. Dallinger. 189 



might be none, or that the small quantity I could obtain of the 

 organisms would make the discovery hopeless. 



But towards the close of the first set of observations my con- 

 viction that such a stage belonged to the organism was fully 

 established, insomuch as I met with the organism in the curious, 

 but to me, extremely suggestive condition seen in fig. 14, plate V., 

 where we have a distinct blending in part of two normal forms. 

 The bodies were inverted in their relative positions; but in the 

 upper one the flagella were, in a manner quite common to the 

 group, fusing with each other, and with the body as at a, b, c, 

 while the lower organism, d, was swimming with full vigour. 



This observation was made, when nearly all the organisms had 

 died out of my fluid, and although I observed this with the utmost 

 care, I could only see for about an hour the slow absorption of the 

 upper form into the under one, which increased slightly in size. 

 But it fell to the floor of the stage, and after a couple of days 

 observation it was abandoned as dead, 



I had now to wait much over twelve months before I, in any of 

 the very many cultures of the form which 1 had made, succeeded in 

 obtaining it again. It is wholly confined to the nearly exhausted 

 condition, of very powerful putrefaction, kept at temperatures 

 ranging from 85° to 95° Fahr. and it is then extremely capricious. 



My second find was however fairly copious at first ; and I 

 endeavoured to pursue the inquiry as to this method of fusion. 

 Eepeatedly I met with forms more or less approximately in the 

 condition shown in fig. 14, plate V., and in every case save two (out 

 of eleven) with the definite result I will describe immediately, but 

 I was only successful three times in finding an earlier condition of 

 this act of blending in all the period of my observation. 



This earher stage is fairly represented by one of the three, 

 shown at fig. 15, plate V., where the two forms are in direct contact, 

 and all the flagella are intact. Their movement was vigorous, and 

 somewhat irregularly alternate ; the flagella of one only being in 

 action at once, until in one of the cases the flagella entangled and 

 anastomosed with each other, and fused with the body as seen in 

 fig. 14; then the other one assumed the horizontal position and 

 swam freely ; and slowly, the upper one was lost in the increasing 

 sarcode of the lower until "each was melted into other." But 

 there was no loss of swimming power. The motion was much 

 slower, almost at times only a spinning on a perpendicular axis ; 

 but the body became vacuoled, and internally segmented in a rapid 

 manner, but not easily discerned in the process from the movement 

 of the mass. 



In all preceding cases the sac of which this was the equivalent 

 had been quite inactive at this stage : but in this case motion was 

 unbroken, and in the course of from four to five hours a distinctly 



