I 



The Microscope. 37 



AN INSECTIVOROUS PLANT. 



KITTIE H. REYNOLDS. 



N the Popular Science Monthly for July, 1883, our common 

 garden petunia was spoken of quite positively as an insectiv- 

 orous plant, and I appointed myself detective to ascertain 

 whether or not we were harboring in our garden a plant with 

 this murderous propensity. 



I observed with the naked eye that most of the stalks of 

 the petunia seem to be covered with minute bits of dirt. I 

 selected one of the dirtiest looking stems, and placing it under 

 the microscope, found that, while there were some particles of 

 inorganic matter caught in its sticky hairs, the majority of the 

 dark specks were, in reality, diminutive insects in all stages of 

 intoxication, death and decay. There were flies, spiders, and 

 various plant pests, some struggling, some dead, and numbers 

 reduced to dry skeletons. Those which were still living really 

 seemed to be prevented from stepping about very lively by 

 something sticky on their feet. 



The hairs of the petunia are naturally erect, slender, and 

 tapering, and each bears at the top an egg-shaped gland. Where 

 the insects had stepped the glands were flattened, or sometimes 

 drawn out into sticky threads, and the hairs were broken or 

 bent. 



A little fly walked across the table, and I escorted him to 

 the stem under the microscope. Before many seconds he be- 

 gan to lift his feet like a boy on stilts. Though I watched 

 closely, I couldn't see that the hairs became excited and moved 

 spontaneously, as was stated in the article which incited my 

 inquiries. The fly raised his feet and burst the glands, setting 

 free their viscid secretion. He fluttered his wings, with the 

 same result. Then he put down his feet and folded his wings, 

 and they stuck fast. Often in his struggles different parts of 

 his body became glued to the hairs themselves, and he dragged 

 them after him. This gives to some of the dead insects the ap- 

 pearance of having been forced down and held by the hairs ; 

 but their imprisonment seems to be the result of their own 

 movements. The more they struggle, the greater the number 

 of glands which they burst and the more firmly they are pin- 

 ioned. 



