POPULAR MISCELLANY. 



141 



usually only a few degrees, it is sometimes as 

 much as ten degrees ; when the temperature 

 of the air falls below the freezing point and 

 continues to fall, the internal temperature of 

 a tree descends to a point near that where wa- 

 ter of vegetation freezes and continues there 

 stationary. Water of vegetation freezes a few 

 tenths of a degree below the freezing point 

 of water. The absolute maximum in the in- 

 terior temperature of a tree trunk may be 

 produced a considerable time before the 

 maximum of the surrounding air, in conse- 

 quence of the direct action of the spring sun 

 and air on the leafless trees. During the 

 high summer heats the internal temperature 

 of trees is nearly steady at about 15 C., 

 with a variation of two degrees or more, even 

 under exceptional conditions of variation in 

 the temperature of the air. A large tree is 

 usually a little warmer than the air in the 

 cold months, and a little cooler than the air 

 in the warm months. 



Anatomy and Physiology for Young Men. 



Writing to the projectors of the Quarter- 

 Century testimonial book to Prof. Burt G. 

 Wilder, Dr. Andrew D. White refers to one 

 point on which Prof. Wilder in the early 

 days was able to render a special service out- 

 side of his chosen field. " While the uni- 

 versity was in its earliest beginnings, a sort 

 of nebulous state, I was impressed by a re- 

 mark by Herbert Spencer, in his book on 

 Evolution, as regards the relative values of 

 different kinds of knowledge. He named, 

 among the things to be taught to young men, 

 human anatomy and physiology ; and his 

 arguments seem to me now to be absolutely 

 conclusive. For apart from the practical 

 part of these studies, they seem to form a 

 most stimulating beginning to study in natu- 

 ral history generally, not perhaps the logical 

 beginning but the best practical beginning, 

 as is shown by the fact that in all ages the 

 great majority of students of note in natural 

 science have been physicians. Under the in- 

 fluence of this impression I asked Prof. Wil- 

 der to give a course of lectures every year 

 to the freshman class on anatomy and physi- 

 ology. Various arguments might have been 

 used against this ; it would have been said 

 that, later in their course, students would 

 have been better prepared to appreciate the 

 tine points of such lectures, and the example 



of all the older institutions might have been 

 pointed to in which such lectures, when given 

 at all, were generally given as a hurried 

 course in the senior year. But the idea of 

 making an impression in favor of studies in 

 natural science, and especially in human 

 anatomy and physiology, just when young men 

 were most awake to receive them, carried the 

 day with me, and hence my request to Dr. 

 Wilder. He acceded to it at once, and for 

 several years, in fact, until the pressure of 

 other duties drew him from this, he con- 

 tinued these lectures, and it turned out that 

 I had builded better than I knew ; not only 

 did the lectures produce admirable practical 

 results, not only did they stimulate in many 

 young men and women a love for natural sci- 

 ence and give them an idea of the best meth- 

 ods in its pursuit, but they made a most 

 happy literary impression upon the students 

 generally ; the professor's wonderful powers 

 of clear presentation in extemporaneous lec- 

 tures proved to be a wonderful factor in 

 literary as well as scientific culture. There 

 was another theory of mine proved to be 

 true by the professor ; for I had often felt 

 that mere talks about literature, mere writ- 

 ing of essays, the mere study of books of 

 rhetoric, were as nothing in their influence 

 on the plastic minds of students compared 

 with lectures thoroughly good in matter and 

 manner given in their hearing day after day. 

 Xaturally I have always felt exceedingly 

 grateful to Prof. Wilder for proving that 

 theory true and at the same time rendering 

 a great service to his students and to the 

 university." 



Preparation of Collections. In his re- 

 port of the Department of Botany and For- 

 estry in the State Agricultural College of 

 Michigan, Prof. W. J. Beale gives a list of 

 the more common mistakes which young col- 

 lectors are apt to make in preparing their col- 

 lections, the perusal of which may give hints 

 of the manner in which the work should be 

 done. They are : The specimen is a mere 

 " snip " of a thing, one little top, destitute 

 of lower leaves, of roots, and root stalks, in- 

 stead of enough to fill completely a whole 

 sheet. In many instances the plant is pulled 

 into small pieces, and runners, sterile shoots, 

 old leaves, etc., are thrown away ; specimens 

 lack fruit, which is often of more importance 



