1878.] 



President's Address. 



61 



The remarkable theory of Schwendener, now ten years old, 

 astonished botanists by boldly sweeping away the claims to auto- 

 nomous recognition of a whole group of highly characteristic 

 organisms — the Lichens — and by affirming that these consist of asco- 

 mycetal fungi united in a commensal existence with Algae. The con- 

 troversial literature and renewed investigations which this theory has 

 given rise to are now very considerable. But the advocates of the 

 Schwendenerian view have gradually won their ground, and the 

 success which has attended the experiments of Stahl in taking up the 

 challenge of Schwendener's opponents and manufacturing such 

 lichens as BJndocarpon and Thelidium, by the juxtaposition of the 

 appropriate Algae and Fungi, may almost be regarded as deciding the 

 question. Sachs, in the last edition of his Lehrbuch, has carried out 

 completely the principle of classification of Algae, first suggested by 

 Cohn, and has proposed one for the remaining Thallophytes, which 

 disregards their division into Fungi and Algae. He looks upon the 

 former as standing in the same relation to the latter as the so-called 

 Saprophytes (e.g. Neottia) do to ordinary green flowering-plants. 



This view has especial interest with regard to the minute organisms 

 known as Bacteria, a knowledge of the life-history of which is of the 

 greatest importance, having regard to the changes which they effect 

 in all lifeless and, probably, in all living matter prone to decom- 

 position. This affords a morphological argument (as far as it goes) 

 against the doctrine of Spontaneous Generation, since it seems 

 extremely probable that just as yeast may be a degraded form of some 

 higher fungus, Bacteria maybe degraded allies of the Oscillatorice which 

 have adopted a purely saprophytal mode of existence. 



Your " Proceedings " for the present year contain several important 

 contributions to our knowledge of the lowest forms of life. The Rev 

 W. H. Dallinger, continuing those researches which his skill in using 

 the highest microscopic powers and his ingenuity in devising experi- 

 mental methods have rendered so fruitful, has adduced evidence which 

 seems to leave no doubt that the spores or germs of the monad which 

 he has described differ in a remarkable manner from the young or 

 adult monads in their power of resisting heated fluids. The young 

 and adult monads, in fact, were always killed by five minutes' 

 exposure to a temperature of 142° F. (Gl° C), while the spores 

 germinated after being subjected to a temperature of ten degrees 

 above the boiling point of water (222° F.). 



Two years ago, Cohn and Koch observed the development of spores 

 within the rods of Bacillus subtilis and B. anthracis. These observa- 

 tions have been confirmed, with important additions, in these two 

 species by Mr. Ewart, and have been extended to the Bacillus of the 

 infectious pneumo-enteritis of the pig, by Dr. Klein ; and to Spirillum 

 by Messrs. Greddes and Ewart ; and thus a very important step has 



