XVII.] linsser's aliquote. 293 



of measurement, for it is only necessary that it shall 

 have, approximately, the same comparative value in 

 all cases. Linsser's constants, being quotients, are 

 small numbers, and are therefore handj^ to use, and 

 they are probably also nearer the true physiological 

 constant than any unit yet proposed. I therefore 

 recommend their use. For myself, I do not believe 

 that it is possible ever to express a life -event in 

 degrees of temperature, from the simple fact that these 

 events are influenced by a multitude of climatal en- 

 vironments. It is quite as easy to express an event 

 of climate by means of a plant -constant, as to attempt 

 to express an event of plants by means of a climate - 

 constant. But these inter -relationships are just the 

 problems which climatological phenology should at- 

 tempt to solve ; and in the collection and tabulation 

 of data to that end, Linsser's aliquote may be used to 

 advantage. 



2. The Climatal Modification of Phenological Phe- 

 nomena. — Whilst the science of phenology has for its 

 first and prime object the study of climate in terms 

 of plant or animal life, it has an important secondary 

 bearing upon the study of botany and zoology. In 

 fact, in most phenological observations the control- 

 ling motive has been simply to determine the life- 

 events of plants and animals as a contribution to 

 natural history, and without having coincident records 

 of climate the observations possess small value to the 

 climatologist. Yet, before adequate climatological rec- 

 ords of life -events can be made, the observer should 

 acquire a fair understanding of the most apparent 

 ways in which climates modify the epochs of living 

 objects. Some of the general directions in which cli- 



