INTRODUCTION. 
17 
amoeboid movements, but do nob produce a flagoUum, and aggregate 
without coalescing into a true plasmodium, has ah-eady been 
referred to (p. 1). The view held by de Bary that the Mycetozoa 
are more closely associated with the Protozoa is supported by a 
comparison with the pelagic Protomyxa of Haeckel, which is 
stated to develop a plasmodium by the coalescence of swarm- 
spores, and differs from the Mycetozoa chiefly in the absence of 
a firm spore membrane;* also by comparison with Bursulla, 
which, according to Sorokin, forms a true plasmodium and minute 
sporangia on horse dung ; the spores do not become invested with 
a firm membrane, and escape from the swollen apex of the 
sporangium in the form of swarm-cells, without cilia, but capable 
of amffiboid movement.f Zopf extends the Mycetozoa so as to 
embrace the Monadineoi of Cienkowski, but de Bary maintains 
that whatever may be the points of agreement between the 
Monadinece and the Mycetozoa they are not such as to warrant 
theu' being classed with the latter cUvision as defined by himself.J 
Lankester accepts the group as defined by de Bary, and places 
them in his grade Gymnomyxa of Protozoa; he suggests their 
affinity with the ySporozoa.\ 
The ingestion of bacteria by the swarm-cells appears to 
strengthen the view that the group is more nearly associated 
with the lower forms of animal than of vegetable life, and 
the name of Mycetozoa appears to mark its true position in the 
borderland between the two kingdoms. For a more complete 
discussion of this subject I must refer to those who have paid 
special attention to the allied groups. 
In preparing this catalogue of the collection of Mycetozoa in 
the British Museum, the arrangement of orders and genera given 
by Rostafinski in his Monograph || has been mainly followed, 
with such alterations as observations made during recent years 
have rendered necessary. De Bary made the group the subject 
of minute and thorough investigation ; IT and Rostafinski, while 
studying under him at Strassburg, devised a system of classification 
which is clear and comprehensive, and is now generally accepted. 
The division by Rostafinski of the main section Endosjjorece 
into two parts, distinguished by the colour of the spores, has been 
objected to as being artificial and wanting in universal applica- 
tion, but the cases in which species offer difficulty with regard to 
their position under this scheme are few, and on the whole the 
organisms range themselves under the separate heads in a re- 
markably natural manner, while for determining the species 
the plan is simple and convenient. 
* De Bary, I.e., p. 449. 
f Ihid., p. 446. 
X Thid., p. 448. 
§ Zoolop;ical Articles, 1891, pp. 11, 20. 
II Slu7,o\vce (Mycetozoa) Mouograpliia (Paris : 1875). 
^ Comp. Morph. and Biol. Fungi, Mycetozoa, etc., p. 421. 
2 
