HARDWICKE'S SCIENCE-GOSSIP. 



83 



STELLATE HAIRS OF PLANTS. 



\ LTHOUGII from time to time vegetable hairs 

 -^*- have formed the subject of short papers in the 

 images of Science-Gossip, there are still many ex- 

 quisite examples to be found on the most lowly of 

 the plant creation which are passed by unheeded 

 by many. 



The most wonderful and attractive forms are the 

 " stellates," some of which have already been no- 

 ticed. A splendid example, however, is found on a 

 low-growing herbaceous plant, bearing yellow 

 ilowers, named Onosma- tauricum ; the whole plant, 

 which grows in rough stony places in its native 



\ 



Fig. 49. Hair of Onosma tauricum, x go. 



habitat, being covered with the very remarkable 

 hairs shown by fig: 49, which give it a very rough 

 feel to the touch. They are large enough to be 

 visible to the unassisted eye ; the longer ones on 

 the under side of the leaf, measuring on the aver- 

 age as much as T V of an inch between the extreme 

 tips. Under the microscope they appear to be 

 composed of the clearest crystal, and nothing can 

 exceed the beauty of these gems, whether regarded 

 singly or arranged in their unvarying plan on either 

 side of the leaf ; the somewhat opaque whitish ex- 

 crescences at the base of each branch of the star 

 are prominent, and form one of the most striking 

 features of this hair. The central spine is much 

 longer than those forming the rays, and in the living 

 plant stands almost erect. Its surface is tubercu- 

 lated, resembling the spicules of Gorgonia. The 

 whole hair is so firmly attached to the cuticle that 

 it cannot be separated without removing a portion 

 of that with it. 



Pig. 50 is a beautiful oblongo-stellate hair, taken 

 from the leaf of Alyssum alpestre, a native of the 

 Pyrenees and mountains of Switzerland. The whole 

 plant is covered with these splendid hairs, giving 

 it a silvery appearance. 



Fig:. 50. Hair of Alyssum 

 alpestre, x 90. 



Fig. 51. Hair of Alyssum 

 spinosum, x 90. 



A single leaf is a most beautiful and interesting 

 object under the microscope, with 1-inch objective, 

 and brilliantly illuminated ; the hairs themselves are 

 covered with nodular protuberances similar to those 

 of Onosma and equally crystalline in appearance. 



Pig. 52 is taken from Alyssum montanum. These 

 hairs are somewhat similar in appearance to the 

 preceding, but more complex, having eight arms, 

 each furcated, and of varying lengths. They are 

 somewhat smoother than those of A. alpestre. 



Fig. 52. Hair of Alyssum montanum, x 90. 



Alyssum spinosum has hairs smaller and more 

 nearly approaching the stellate type, fig. 51. They 

 cover the plant very thickly, giving it a glistening 

 or frosted appearance. 



The real use of these beautiful leaf-appendages 

 seems to be somewhat obscure ; but may they not 

 be of value in determining the species of plant, to 

 which they belong? 



Fulham. John Carpenter. 



Acorns.— John Ellis has discovered that acorns 

 can be preserved in a state fit for vegetation for a 

 whole year, by enveloping them in beeswax 

 other seeds may be conveyed from distant countries 

 by the same means. — Phillips, "Fruits of Great 

 Britain." 



