SCIENTIFIC COMMITTEE, APRIL 12. 



xxvii 



the introduction of new sorts, have failed as remedies. The 

 fungus causing the mischief has been recognised by Mr. Massee as 

 a Dothidea (? D. rosa). 



Narcissus Bulbs attacked by Acari. — Mr. Michael reported 

 upon the bulbs received from Kev. W. Wilks as follows : "I find 

 two species of Acarus in large numbers, either of which is suffi- 

 cient to account for the damage. Both are most injurious 

 creatures, and commence destruction upon healthy plants. One 

 is the large and conspicuous Ehizoglyphus (species probably 

 Echinopus, but there was no adult male specimen, without which 

 the species cannot be determined for certain). This is a well- 

 known destroyer of bulbs. The other, which occurs in great 

 numbers, is extremely minute, and not to be detected without a 

 microscope. It is a Tarsonymus ; the species is most like 

 T. oryzae (of Targioni-Tozzetti). All species of this genus are 

 most destructive. It is only of late years that their existence has 

 been detected, on account of their small size, the transparent and 

 colourless nature of their bodies, and their habit of burrowing 

 into leaves, stalks, &c. I should say that in this case they were 

 doing even more damage than the Ehizoglyphus. This is, I 

 believe, the first instance of Tarsonymus being found in subter- 

 ranean structures. A species of this genus, T. Buxi, destroyed 

 every Box-tree in Turin. Tarsonymus is well known to be very 

 destructive to Sugar-canes in Barbadoes and Queensland." A 

 discussion followed as to the best remedies to be applied. Mr. 

 Michael suggested a treatment of soap and sulphur before plant- 

 ing, but added that it is almost impossible to destroy the eggs by 

 chemical agencies. Mr. Wilks observed that, since it is not till 

 springtime when the eggs are hatched, the application would be 

 difficult, seeing that the bulbs are planted in the autumn ; more- 

 over, Mr. Dod has shown that one effect of sulphur upon bulbs 

 is to arrest their growth by the formation of sulphurous acid gas. 

 The Bev. Mr. Haydon had suggested, in his lecture on Daffodils, 

 the use of powdered quicklime, and although this might destroy 

 the outer scales as well as the eggs which lie among them, 

 experiments with bulbs of comparatively little value would 

 show whether the interior portions remained uninjured. Mr. 

 McLachlan suggested paraffin. Mr. Wilks remarked, however, 

 that this remedy, though excellent for aerial organs, was fatal to 

 roots, but whether it would be equally injurious to bulbs could 



