94 



Bromley, Kent, and Mr. A. M. Massee, of Sevenoaks, were elected 

 members. 



Captain J. Kamsbottom, F.L.S., gave a lecture on " The Sym- 

 biosis of Fungi with the FertiUzation of Orchids," and illustrated 

 his remari<s with lantern slides and diagrams. 



The following is an abstract of his remarks. 



" The lecturer began by remarking on the living together of 

 different organisms, each benefitting from the association. This 

 phenomenon is known as " Symbiosis." Examples were mentioned 

 such as a lichen, association of fungus and alga ; ginger beer plant 

 (Californian Bees) yeast and bacteria ; bacterial nodules on roots of 

 peas, beans, and other leguminous plants. An exceedingly common 

 example is the association of fungi with the roots of flowering 

 plants. There are two types of fungus root or mycorhiza ; one 

 which is frequent in forest trees where the fungal hyphae occur as 

 a mantle around the roots, and the other in such plants as heather 

 and orchids, where the fungus mycelium is within the tissues of the 

 root. The case of the orchid was then considered in detail and 

 illustrated by lantern slides. It has long been known that orchid 

 seeds are very difficult to germinate, in fact, they will not germinate 

 in the usual way, but a certain amount of success is obtained by 

 sowing them on the soil containing the parent plant. Bernard, a 

 French observer, found that if the fungus was extracted from the 

 roots of the orchid and grown in pure culture, and the seeds planted 

 thereon, the majority of them germinated. This explained the 

 previous failure. The fungus is necessary before germination can 

 take place. The seed of orchids, unlike most plants, does not show 

 a differentiated embryo- or baby plant. The cells at one end of the 

 seed are, however, usually larger than those at the other. When 

 the seed is sown on the medium containing the fungus the threads 

 of the latter pass into the larger cells. Development then proceeds. 

 The small cells at the further end of the seed undergo rapid division 

 and the growing point of the stem is laid down and leaves given oflf 

 in succession. After a short time the growing point of the root 

 appears and the young root absorbs its way through the swollen 

 tissues, and finally becomes free, and in doing so misses the zone of 

 tissue containing the fungus. It thus happens that the young root 

 is at first quite free from the fungus, but after a short while becomes 

 infected from the soil. A culture of the fungus and a flask con- 

 taining an enormous number of orchid seedlings was exhibited. 

 Slides showing the culture houses at Messrs. J. Charlesworth's 



