J24 FREAKS OF PLANT LIFE. 



and must appeal to his work for the details of his 

 discovery. 



Thirty-nine leaves with objects adhering to them 

 were sent from North Wales. Thirty-two of these 

 had caught no less than 142 insects. Subsequently 

 nine plants, bearing 74 leaves, were forwarded, and all 

 <;f these latter, except three young leaves, had insects 

 adhering to them. Another consignment of plants 

 from Ireland had insects on 70 out of 157 leaves. 

 Most of the insects were diptera, or two-winged flies. 

 Circumstances such as these, presented in such a 

 forcible manner to an investigator like Mr. Darwin, 

 would naturally suggest to his mind the inquir}-, 

 *' why, and how, are these insects caught .-' " 



An examination of the structure of the leaves 

 showed that the upper surface was thickly covered 

 with glands of two kinds, (i) Large circular glands 

 divided into sixteen cells, and supported upon 

 elongated peduncles, or footstalks ; and (2) smaller 

 glands of a similar character on shorter peduncles. 

 All the glands secrete a colourless sticky fluid, so 

 viscid that it may be drawn out in threads for a foot 

 or eighteen inches. The edges of the leaves are 

 devoid of glands. Here, then, is sufficient cause for 

 insects and other objects being found adhering to 

 the leaves, as flies may be seen sticking to the old 

 fiashioned fly-papers. So that the plant deserves to 

 be considered a " fly-catcher." 



