BOTANICAL GAZETTE. 



297 



olis and enjoy the quickening influence of the exchange of opinions, and of so- 

 cial intercourse, and the increased attendance is accounted for. 



A strong attempt was made to have excursions for the particular benefit ol 

 the botanists, but owing to the difficulty of learning the plans of the local com- 

 mittee in time to make corresponding arrangements, and duly notify those in- 

 terested, the attendance upon such as were arranged was small, much to the re- 

 gret of all concerned. Those who were so fortunate as to go, both specialists 

 and general collectors, were enthusiastic over their success in obtaining desir- 

 able specimens. 



This experience in conserving the interests of botanical members led to the 

 conviction that to insure the best results there should be well-matured plans 

 developed before the Association convenes, and which should be so arranged as 

 not to conflict with other excursions or exercises. A committee was accord- 

 ingly appointed to attend to the matter for the Philadelphia gathering of next 

 year, when we may expect still larger attendance and more profitable herbor- 

 izing. — J. C. A. 



Chlorophyll corpuscles and Pigment bodies.— Every student of plant 

 histology knows how impossible it is often to speak definitely with regard to 

 cell contents. Attempts have been made to classify them, but only in well 

 marked cases are they satisfactory. When any system finds its best exemplifi- 

 cation only in exceptional cases it is time to look for another. Schimper, at 

 Bonn, and Meyer, at Strassburg, have been working independently at certain 

 phases of this problem, and have reached a more resonable conclusion than has 

 ever been heretofore advanced. It looks as though the principal contents of 

 cells, as varied as they appear, all have a common origin, that starch-formers, 

 chlorophyll corpuscles and pigment bodies are related forms, sometimes even 

 interchangeable, and are not produced in the protoplasm of the cell. This last 

 statement is a regular iconoclast, for if we have ever taught anything with con- 

 fidence about cell contents, it has been that we would have to look to proto- 

 plasm as the originator of most of them, that a chlorophyll corpuscle was noth- 

 ing but colored protoplasm, that starch -formers were in some mysterious way 

 born in protoplasm and chlorophyll, etc. But now those nameless little floating 

 bodies, specks, needles, rods, etc., to which we have called no special attention, 

 are all these things in various stages of formation, are called plmtidia or plastids, 

 and have existed from the very first in the plant, in the embryo itself, even in 

 the embryo-sac and oosphere. Of course they are protoplasmic, are always 

 present in meristems, and by the continuous growth and division of a few 

 primitive plastidia the whole plant is supplied. This reduces the nomenclature 

 of cell contents to a more uniform basis, but of course this common origin 

 allows names to be applied rather to marked phases than to things which are 

 specifically distinct, and allows every intermediate stage. Thus leukoplaste nor- 

 mally come from colorless plastidia in deep-seated cells, or may be from rhloro- 

 plasts, or may under the action of light become cMoroplasts, or may act as 

 Schimper's Starkebildiier. CMoroplasts (chlorophyll copuscles) come normally 

 from plastidia which are originally green, but they may come from leukoplasis 

 exposed to the light, and often become cfkomoplasts (the pigment bodies). Chrom- 



