13 



are being kept under cultivation in Washington and New York. 

 Numerous species from Arizona, New Mexico, Lower California 

 and the West Indies have been secured by expeditions sent out 

 by the New York Botanical Garden and now are under cultiva- 

 tion in New York. Herbarium material is, as a rule, peculiarly 

 inadequate to a proper appreciation of the relationships of the 

 members of this family and it is hoped soon to have all of the 

 North American species under observation in the living state. 

 Herbarium specimens are being supplemented by photographs 

 and by material preserved in fluids. 



The most recent of the more important papers on the classifi- 

 cation of the Cactaceae is one by Berger, entitled "A Systematic 

 Revision of the Genus Cereiis Mill." and published in the Six- 

 teenth Report of the Missouri Botanical Garden (1905). This 

 paper has been based chiefly on the studies made in Sir Thomas 

 Hanbury's famous gardens in Itah', and gives much importance 

 to characters of flowers and fruit, characters which have been 

 largely ignored in previous schemes of classification because un- 

 known. The genus Ccrciis is divided into eighteen subgenera 

 by Berger. The studies of the speaker and of Dr. Rose indicate 

 that both in the old genus Cerciis and in other groups of the 

 cactus family, well-marked differential characters of flower and 

 fruit are coordinated with those of the stem in such a way as to 

 make the recognition of several new genera natural and con- 

 venient. After these introductory remarks, the meeting was 

 adjourned to the propagating houses of the Garden, where nu- 

 merous living specimens of Cactaceae were demonstrated and 

 commented upon. Of the genus Ccreiis in the current sense, 

 various types representing subgenera or possible generic segre- 

 gates were discussed. Among these were Cernis penivianus, 

 the proper type of the genus Cereiis ; species of the Pilocereus 

 group, with which the older Ccphalocerens is historically iden- 

 tical ; Ccreiis ScJiottii of Berger's subgenus Lopliocereiis ; Cereiis 

 geometrizans, representing Console's genus Myrtillocactns ; Cereiis 

 Pringlei of Berger's group Pachycereiis ; Cereiis soiwrensis, repre- 

 senting Stenocereus, also of Berger ; Cereiis triangularis, a spe- 

 cies much cultivated in the West Indies and southern Florida, 



