Plant Families : A Plea for International Sequence. 271 
(*'). Whether groups such as Mimosece , Clusiece , Cichoriece 
etc. should be considered as families; 
(/). Whether Alismacece are the primitive monocotyledons; 
( k ). What are the relationships of the Palmce ; 
(/). Whether Aracece are related to Piperacece. 
Summary. 
The present article may be briefly summarized: 
1. A periodic inventory of facts and opinions which appear to 
have a bearing on the sequence of families, especially of living 
vascular plants, is greatly to be desired. 
2. Where facts are not conclusive the definite goal of a truly 
international sequence should be sought through agreement. 
3. Standard numbers as part of symbols for plant families, 
revised at suitable intervals, would serve important practical 
purposes, especially in the co-ordination of information. 
In conclusion it may be said that if it should be widely agreed 
that an international family sequence were desirable, ways would 
doubtless be found to overcome the various difficulties in the way 
of its establishment. Discussion of the subject by those interested 
might be a first step. 
Brooklyn Botanic Garden. 
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