TEMPERATURE OF FUNGI. 



iiigs of the thermometer were made at 8.45 a.m. 

 aj^ain observed at 10.30 a.m. and 11.15 a.m. 



337 



The temperature was 



Next morning two readings were taken at 9.10 a.m., the Fungus being 

 warmer than the surrounding atmosphere. 



On the next morning the Fungus was found to be drying up, and the 

 observed temperature was only 0"2° higher than that of the surrounding 

 air. The air outside the box, 11"4°; inside the box, 11'4°; temperature 

 of Fungus, 11 '6°. No further observations were made. 



A. de Bary mentions (lloft'meister, ' Handbuch der Physiologischen 

 Eotanilc,' voi. ii. pt. 1. p. 228) that the temperature has been observed 

 by Dutrochet in five Fungi belonging to the genera Atjaricus, Boletus, and 

 J,ycoperdon. He. however, was only able to observe an increase of from 

 0"10° C. to 045° C, The greatest increase in ray specimen was noticed 

 on the first morning of the observations, at 8.45 a.m., namely 1'2° C. 



The greatest temperature is evidently produced during the night, as the 

 difference between the temperature of the Fungus and air rapidly dimi- 

 nished, so that at 11.15 a.m. the difference was only 0"2° C. 



The difierence between the morning temperatures on the first and second 

 day of the observations — 1'2° and 0'9° — can be easily accounted for by 

 loss from conduction, etc., biit chiefly from the loss of heat caused by the 

 evaporation of Avater, the weight of the Fungus having decreased from 

 16 oz. to 13^ oz. during the three days the experiments lasted. 



The cause of the increase of temperature is due to the oxidation of the 

 nutrient materials in the Fungus, a process depending on the absorption 

 of oxygen, which acts on these nutrient materials, and causes various me- 

 tamorplioses, an equivalent quantity of carbon dioxide being liberated. 

 This metamorphosis of nutrient or assimilated materials goes on in all 

 plants in dayliglit as well as in darkness, and is also associated with the 

 taking up of oxygen and liberation of carbon dioxide, a process which is 

 now recognized by all Continental ])hysiologists as the true respiration of 

 plants. In Spirogyra we can, during the day, observe the formation of 

 assimilated materials as starch in tiie cells, which contain chlorophyll. 

 During thenitiht the assimilated material is metamorphosed or elaborated, 

 and the cell divides and converts the assimilated material, after it has 



VOL. IX. [novembeh i, 1871.] z 



