MARSH EQUISETUM. 
47 
in a catkin of uniform size witli the others, as rej^resented in the 
figure, which is drawn from an exceedingly beautiful specimen, 
kindly lent me by Miss Griffiths. At other times the stem bears 
a catkin of the normal size and form, while those on the 
branches are comparatively diminutive in size : for specimens 
of the latter form I am indebted to several kind correspondents. 
1 may remark that the catkins in this form of the plant are 
usually small, and in the specimens which have come more 
especially under my notice, they are very black and compact. 
