21 8 LISTER : THE STUDY OF MYCETOZOA IN BRITAIN. 
This was increased when, some years later, Prof. I. Bayley 
Balfour lent him for examination the valuable collection he 
had acquired while working under De Bary at Strasburg, which 
consisted to a large extent of portions of Rostafinski’s types. 
Permanent mountings and drawings were made of all the more 
striking specimens and served as a priceless standard for reference. 
Meanwhile, microscopic work was backed by observations 
made in the field at all times of the year. A store ol information 
was collected on the changes induced in maturing sporangia by 
differences of heat and cold or o i drought and moisture. In 
this way it was found that many curious forms which had 
been considered distinct species were in reality well-known 
species altered by weather conditions 
It was in 1891, while looking through the collections in 
the British Museum, that my father was asked by Mr. Carruthers, 
the head of the Botanical Department, to prepare a Descriptive 
Catalogue of the Mycetozoa 1 in their herbarium. To fit himself 
more thoroughly for this task, he visited Strasburg, in order 
that he might see De Bary’s collection, and stayed at Kew 
to examine Berkeley’s herbarium preserved there. The 
Mycetozoa belonging to the Paris Museum and those of Mr. 
Massee’s collection were courteously lent to him for examination. 
For years, the circle of friendly correspondents at home and 
abroad with whom specimens were exchanged and discussed 
was gradually enlarging, and invaluable help and experience 
was obtained in this way. At every stage in the preparation of 
the Catalogue, my father received assistance from the officials of 
the British Museum. Mr. Carruthers himself undertook to trace 
the history of the literature of the species and to adjust the 
nomenclature that it might accord with the rules then in force. 
It was my privilege to companionate and help my father 
in his work, including the preparation of the plates. Those 
in the first edition of the Catalogue, which appeared in 1894, 
are photographic reproductions in black and white of our coloured 
drawings. Better results were obtained in the second edition, 
which appeared eighteen years later. For a large proportion of 
the drawings in this edition, the three-colour process of repro¬ 
duction has been employed. 
7 A Monograph of the Mycetozoa ; being a Descriptive Catalogue of the Species in the Her¬ 
barium of the British Museum (1894). 
