66 H. MARSHALL WARD. 



atmosphere outside the liquid. On the sides of the bulbs, or on the 

 leaves, and generally on any part of the Hyacinth exposed to the dry 

 air outside, the sporangia are not developed, and every attempt to 

 cultivate them there has so far failed utterly. 



There can be no doubt that the life-history of this Myxomycete then 

 is passed through in the aqueous solution, and it seems to me a point 

 of no small interest to have found what may justly be described as an 

 aquatic Myxomycete. 



There is still another point of general importance to be mentioned. 

 The sporangia arise on what are to all intents and purposes perfectly 

 healthy, living, and intact roots, and there are no observations to show 

 that the organism causes any injury whatever to the plant on which 

 it is found. It is not intended to deny that this Myxomycete may 

 produce its sporangia on dead or dying roots — a point which I have 

 not directly investigated, though some experiments to be described 

 later show that it may well be so — but all investigation places beyond 

 doubt that no interference with the normal relations of the root are 

 necessary for the well-being of the Myxomycete. 



The black sporangia referred to contain spores ; these spores ger- 

 minate readily and emit " myxamoebse," which pass rapidly into 

 " myxozoospores" ; after a varied term of life, during which nutrition 

 is carried on, and various phenomena connected with reproduction are 

 observed, these " myxamoebee " unite into plasmodia ; which, in their 

 turn, again form sporangia. The above may be regarded as a cursory 

 sketch of the life-history which I have observed point for point, and 

 partly because the above headings agree broadly with the order of inves- 

 tigation, and partly for other reasons, I shall adopt the simple plan of 

 describing the subsequent details in the following order. (1) The 

 anatomy of the sporangium and its contents ; (2) the germination of 

 the spore, and the production of myxamoebse ; (3) the changes under- 

 gone by the myxamoebse — their nutrition, changes of form, encystment 

 and division; and (4) the formation of the plasmodium, and the 

 changes which it undergoes. Other remarks, on the physiology of 

 the myxamoebse chiefly, may find place under one or more of the above 

 headings. 



The Sporangium. 



As shown in fig. 1, the sporangium is a minute black body, of 

 globular or ovoid form, or occasionally less regular and shaped like a 



