266 Transactions of the 



himself arrested by another kind of phenomenon. Some of the 

 normal forms become extremely granular at their posterior or non- 

 flagellate end, so that the granules give the protruding effect 

 of an acorn cup. These swim with great freedom, and are gene- 

 rally larger than the other forms. One of them is represented 

 at Fig. 13. Suddenly, and without warning, these swiftly moving 

 bodies shoot out almost the whole mass of granules, and deposit 

 them, as seen in Figs. 14 and 15, leaving the monad almost entirely 

 destitute of granules, and with the hyaline membrane still retaining 

 its shape, but the sarcode within much altered in form and 

 position. This is shown in Fig. 15 ; but also other modifications 

 attending the emission are drawn at Figs. 16, 17, and 18. At 

 certain stages of development thousands of these granular forms 

 are visible in every " dip " of the fluid. At first the extruded 

 granules seem to have no significance ; and they were for a long 

 time a source of great perplexity to us. But we confined our 

 attention at length wholly to these for some time, and by the use 

 of our best appliances were enabled to discover their nature. 

 When deposited, the granules are amorphous, more or less agglo- 

 merated, and perfectly transparent. Watching them attentively 

 with the highest available powers of the ^Vy we at length saw spots, 

 or minute points or dots, appear in the granules, as seen in 

 Fig. 19. These under constant observation increased, and in one 

 of them, as many as seventeen were counted. In this condition 

 they are drawn at Fig. 20. They remained like this for from two 

 to three hours, only slightly increasing in size. At the expnation 

 of this time a vibratory motion of the internal points was per- 

 ceived, which very rapidly increased, and in the course of forty 

 minutes intense internal activity was visible, the minute dots Within 

 the sarcode mo^^ng upon each other in all directions. This lasted 

 from ten to fifty minutes, when they all escaped and at once swam 

 freely as minute bacterial-like bodies, but no trace of any organs of 

 locomotion could be discovered. After they began to move they 

 rapidly increased in size, so that in from four and a half to five 

 hours they were of normal size, and endowed with all the powers 

 of the original monad. This was seen again and again, in all its 

 stages, and the new forms were followed up to the condition of 

 multiple fission, as before described. 



Other phenomena presented themselves, but nothing that we 

 could explain or correlate ; and we were for two years inclined to 

 think that this must be the entire process of development. But 

 commencing again wath fresh working power, we were this last 

 summer enabled to find what gives completeness to this history. 



(3.) We had occasionally seen during the whole period of our 

 researches on this form a coming together of two of the monads ; 

 but from its infrequency and occasional abortiveness, as well as 



