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STATE BOARD OF AGRICULTURE 



was observed in several cases, but only of the small forms. Other types of 

 multiplication probably occur, for undoubtedly the large forms split up into a 

 number of smaller individuals. 



The organisms are not invariably of the long sinuous type; many indi- 

 viduals show only a slight undulation of the body and others are almost 

 straight. The slightly sinuous type of organism is shown in Fig. 9, which is a 

 photomicrograph of a longitudinal section through sieve petiole tissue. In 

 this same figure is illustrated what probably is the phenomenon known as 

 agglomeration, that is, two or more organisms attached to each other by the 

 posterior ends of the body. Among protozoa parasitic upon animals especially 



Fig. 13. Photomicrograph of a very small protozoan closely applied-to a nucleus, which is destained. 

 X 1500. 



A. Protozoan. 



B. Destained nucelus. 



C. Deeply stained nucleus in adjoining cell. 



trypanosomes, agglomeration of individuals is a very common phenomenon. 

 It is supposed to be analogous to agglutinization of bacteria under unfavorable 

 conditions. At first the observation of these organisms in this position is 

 likely to suggest conjugation, but since no definite evidence is available to 

 show that this ever occurs among organisms of this type the rather frequent 

 finding of them in this position is interpreted as representing the occurrence 

 of agglomeration. No explanation is suggested as to its cause, but possibly 

 fixation may be responsible. 



The size of the organisms varies as widely as do young and old individuals 

 of other protozoa. A very small form is shown in Fig. 13. This is apparently 



