30 



THE YOUNG 



NATURALIST. 



is very noticeable in the chickweed 

 order (Caryophyllacea) , to which the 

 common name of catchfly has been 

 applied, as the English catchfly 

 {Silene Anglica), the German catchfly 

 {Lychnis viscaria). These plants are 

 rather local .and may not be easily 

 attainable in a living state ; but the 

 common ragged robin [Lychnis flos- 

 cuculi) exhibits the same peculiarity, 

 although in a less degree. It will be 

 noticed in these plants that certain 

 portions of the stem, particularly the 

 joints where the leaves spring off, are 

 covered with a sticky secretion in 

 which the feet of crawling insects 

 become inextricably entangled, forming 

 to them an impassable morass they can 

 neither avoid nor wade through. Anal- 

 ogous to this defence are the glandular 

 hairs of other plants, such as the 

 stinking groundsel (Senecio sylvaticum) 

 or the viscid groundsel (<S. viscosus), 

 or the sow thistle (Sonchus arvensis). 

 It is well known that a water-moat forms 

 the most impregnable defence against 

 wingless insects, like Tarn o' Shanter's 

 witches : — 



" A running stream they daurna cross." 



And some plants like the common 

 Teasel (Dijosacus) are admirably de- 

 fended by a cup-like cavity formed by 

 the united bases of the leaves which 

 encircle the stem. This receptacle 

 generally contains a quantity of fluid 

 which effectually bars the ascent of 

 adventurous ants. The gardener at- 



tains the same end by encircling his 

 choice plants, such as dahlias, with a 

 vessel containing water— an unbridge- 

 able fosse to earwigs and ants. It has 

 long been noticed that plants growing 

 in water are destitute of hairs : their 

 place of growth securing them immu- 

 nity from wingless marauders, Nature 

 deemed it superogatory to furnish them 

 with defensive weapons as well. In 

 plants which grow indifferently on land 

 or in water, most curious diversities in 

 this respect are seen. Thus the am- 

 phibious bistort (Polygonum amphibi- 

 um), a common plant which is equally 

 at home in " flood or field," when it is 

 growing in water the stems and leaves 

 are quite smooth and hairless, but the 

 same plant when growing on the land 

 becomes covered with a dense coating 

 hairs — an evident provision for an 

 obvious need. The study of this sub- 

 ject opens up a wide field of research 

 to the persevering student. I have 

 purposely omitted all reference to the 

 tentacles of the sundews, as they might 

 more correctly be classified as offensive 

 weapons, and deserve a separate article 

 for themselves. 



THE BIRDS OF DERBY AND 

 NEIGHBOURHOOD. 



By G. W. Pullen. 



Family SYLVIAD^E. 

 Sylvia modularis, Penn. Hedge Sparrow. 



