A. M. Taylor 249 



compacted masses, and all stages from egg to adult are present in 

 them. 



If such colonies are observed in dissected buds kept in a state of 

 normal moisture for a few days, they shew no apparent diminution 

 or increase in numbers, nor do they appear to alter their position in 

 the bud. When, however, they are transferred to water they separate 

 rapidly, and assume the quick wriggling motion characteristic of the 

 group Anguillulidae when immersed in that medium. If, on the other 

 hand, such infected buds after dissection are allowed to dry in the 

 laboratory the worms will be found on examination to have grouped 

 themselves in similar colonies, and to have taken up their position 

 in the scale and outer leaves of the dried buds. They are found in a 

 desiccated and quiescent condition, and the individuals comprising 

 the groups are — instead of being intertwined and straightly extended — 

 intercoiled, and form in many cases circles and figures of eight of the 

 most perfect symmetry, notwithstanding the fact that they are composed 

 of hundreds of individuals. The habit of the nematodes in thus forming 

 colonies and the response of such bodies to the conditions of moisture 

 and drought, are the principal factors which control the migration of 

 the worms. 



It has been observed in the field, and confirmed by experiment, 

 that bud to bud migration, which recurs at frequent intervals throughout 

 the year, depends entirely on the presence of the requisite degree of 

 moisture in the form of rain, mists, or heavy dews, for its successful 

 achievement. This being present, the worms can leave the dead buds, 

 which in their contracted condition allow the water free entrance, 

 and swimming rapidly in the film of moisture which envelops the 

 intervening stem, can either ascend to the unattached buds above or 

 descend to those below. Arrived thus far, there is no difficulty in gain- 

 ing an entrance between the unresisting scale leaves of the bud about 

 to be attacked. 



If, however, drought ensues when migration from a dead bud has 

 become imperative, the worms undergo a period of enforced quiescence 

 and desiccation in the scale leaves till a moist medium once more 

 prevails. If such moisture be forthcoming in the form of light rain, 

 heavy mists, or dews, the worms, after a certain period of immersion, 

 gradually resume their motility, and behave as in the foregoing case. 

 Should, however, torrential or heavy rain fall the desiccated migrants 

 floating on the descending water are rapidly carried to the ground 

 unless some intervening obstacle present itself to detain them. When 



