336 GERANIACE^. [paktii. 



but the alternate ones are longer than the 

 others, and have a gland at the base of each. 

 The seed-pod is said to resemble the head of a 

 crane, and when it bursts, the styles, which are 

 smooth inside, curl up round and round like the 

 coil of a rope. The seeds of many of the kinds 

 are beautifully netted. Many of the species are 

 British weeds, and among the commonest of 

 these may be mentioned Herb Robert {Gera- 

 nium Rohertianum)^ and the Meadow Crane's- 

 bill (G. pratense). Dr. Lindley, in his Ladies' 

 Botany, mentions a curious and beautiful expe- 

 riment which may be performed by pressing the 

 petals of a Geranium between two pieces of 

 glass which have been previously wetted. He 

 says, that by pressing the two glasses firmly 

 together, all the air may be squeezed out of the 

 petal, and it will become transparent. '* You 

 may then," he adds, " with a pretty good mag- 

 nifying power, observe all the air-vessels of the 

 veins distinctly, looking like fine threads of 

 silver-wire twisted up like a spiral spring. It 

 is on account of this appearance that the air- 

 vessels are called, technically, spiral vessels." 

 The experiment appeared to me so easy, and 

 at the same time so interesting, that I tried it, 

 but unfortunately without success; probably 

 owing to the want of power in my microscope. 



