RELATIVES OF THE HERB ROBERT 148 
The Dovesfoot, the Small Dovesfoot and. the 
Shining Cranesbill agree with the Herb Robert in 
ejecting the seed still enclosed in the knob, but 
none of the other three has the long hygroscopic 
threads of Geranium Robertianum. In all of them 
the knob is more or less like an insect, and we should 
notice that the seed itself has a smooth skin in all 
four. 
Things are, however, quite different with the 
Cut-leaved, the Round-leaved, the Long-stalked,* the 
Meadow and some other Cranesbills ; instead of being 
thrown from the elastic spring, which is torn clean 
away from the central rod, the knob remains attached 
to the bottom of the spring, while the spring itself, 
after the throw, still clings by its other end to the 
rod. The seed is held lightly in place by a little 
tuft of hairs that grow over it from the far end of the 
knob, but exactly at the right time, while the spring 
is curling up, the hairs give and the seed is shot out. 
When all the seeds have suffered this fate we find the 
five curled-up springs, still attached to the central 
rod, like the spokes of a coverless umbrella turned 
inside out, with an empty knob at the end of each; 
the tuft of hairs remains although the seed has of 
course gone, and it can then be seen and examined 
quite easily. 
Now, while those species that throw the seed 
enclosed in the knob have the latter more or less 
rough, wrinkled and like an insect, the seed itself being 
smooth, in all those that throw it free the knob 
is not wrinkled, it bears no sort of resemblance to an 
insect, and the seeds are not smooth; on the contrary 
they are beautifully sculptured, although a lens or a 
* Geranium columbinum, Linn. 
L 
