6 FIRST REPORT ON ECONOMIC BIOLOGY. 



part in exposing different plants to the attacks of fungi by the injury 

 they cause in wounding their surfaces. 



Since then two facts have come to light which have an important 

 bearing upon the subject. 



The experiment I made I described as follows : 



" During the past twelve months very careful observations have 

 been made upon a series of common species which have fully estab- 

 lished the fact that to orchids, numerous bulbs, beans and peas, the 

 Collembola are distinctly injurious. 



" The method adopted has been as follows : 



" Shallow boxes, containing about four inches of moist soil, have 

 been used, and into these perfectly healthy bulbs and beans have been 

 placed. Into each box examples of different species of Collembola 

 have been placed. The tops of the boxes in some cases were covered 

 with a sheet of glass, and in others with a piece of wood. 



" After the experiments were completed the soil and diseased 

 bulbs were carefully examined, and apart from fungi no other pests 

 were found, but in all cases the Collembola had increased largely in 

 numbers." 



At the time it did not occur to me to inquire " where did the 

 fungi come from? " But since then this same soil has in part been 

 used to pot bulbs in, and the remainder was thrown on to the garden. 

 In the pots and in the garden where this soil was placed, there is now 

 arising an abundant crop of different fungi. 



As none of the fungi have previously been noticed in the garden 

 and do not now occur, excepting in this restricted patch and in the 

 pots, I think I am justified in concluding that the spores were originally 

 introduced by the Collembola. 



Dr. Buller, 1 in his recent work, states : " The gills of expanded 

 fruit bodies are frequently visited, not only by Fungus Gnats, but 

 also by Springtails (Collembola) . . . Some fruit bodies of Polyporus 

 squamosus, which were growing on a log and had not yet become fully 

 expanded, were infested with small black Collembola. There were 

 as many as fifty to the square inch, and each one occupied a hymenial 

 tube, which was just wide enough to hold it. The Springtails (genus 

 Achorutes), infesting Stropharia semiglobata, and some other species 

 of Agaricineae, were found to contain spores in the mid-gut," and it 

 is well known to students of this interesting order that large numbers 



1 Researches on Fungi, London, 1909, p. 20. 



