481 



to these must be placed the diurnal terrestrial, and last of all the 

 nocturnal terrestrial species. 



In the next division of this paper the author considers the tem- 

 perature of those insects which live in societies ; and in particular of 

 the humble bee and the hive-bee. His observations are confirmatory 

 of many of those of Huber relating to the incubating habits of the 

 former of these species ; and he has farther ascertained that during 

 the act of incubation the bees possess a voluntary power of genera- 

 ting heat, whereby the temperature of their bodies is raised, appa- 

 rently for the purpose of imparting warmth to the young in the 

 cells; that this process is accompanied by accelerated respiration; 

 and that the amount of heat evolved is proportional to the quantity of 

 air respired. The law established by Dr. Edwards in the case of 

 the young of mammiferous animals, namely, that they possess less 

 power of generating heat, and that for a certain time they are unable 

 to maintain their usual temperature, is shown by the author to be 

 equally applicable to the early stage of insect life, and also to the 

 perfect insect immediately after its developement from the pupa. 



The temperature of the hive-bee is next examined, and it is shown, 

 contrary to the statements of Reaumur, Huber, and others, that bees 

 do not maintain a very high temperature in their hives during winter, 

 but that they are disposed, when not disturbed by any occasional 

 vicissitudes of atmospheric temperature, to assume the state of hy- 

 bernation ; although, on the other hand, when the bees are much dis- 

 turbed, the temperature of the hive may, even in the midst of winter, 

 become greatly raised. The temperature of the hive is lowest in 

 January, and gradually increases up to the period of swarming, in 

 May or June, after which time it diminishes. A table is given ex- 

 hibiting the results of successive observations on the influence 

 of the diminution of heat and of light which attended the progress 

 of the annular eclipse of the sun on the 15th of May, 1836, on the 

 temperature of the hive. 



It appears from the inquiries of the author that different parts of 

 the hive do not preserve the same relative heat among one another 

 at different periods, and also that the amount of free heat in the hive 

 is often 10° or 15°, even in the months of July and August. 



The remaining division of the paper is devoted to the considera- 

 tion of the connexion existing between the developement of heat 

 and the functions of respiration, circulation, and digestion. The 

 state of the pulse during all the different stages of the larva until 

 its metamorphosis into the pupa is examined with great minuteness, 

 and the results are given in a tabular form. The author traces the 

 rate of pulsation during different conditions of repose and activity, 

 and the corresponding frequency of respirations, and finds that al- 

 though there is a general accordance between the activity of these 

 two functions, yet that the activity of respiration and the quantity 

 of heat evolved do not depend primarily on the velocity of the cir- 

 culation, but that under all circumstances the quantity of heat de- 

 veloped is exactly proportional to the quantity of respiration. While 

 the insect is feeding, and digestion is going on, the evolution of 



