718 



THE POPULAR SCIENCE MONTHLY. 



of getting at the truth. He is especially 

 liable to be led away by impatience to get 

 results. Preliminary communications are a 

 very great as well as a very prevalent evil. 

 The greed for priority leads many even fine 

 workers far astray. The tendency to specu- 

 late is a third evil, and a fourth is the dispo- 

 sition to accept too readily simple and well- 

 finished conceptions. It is the function of 

 original memoirg to assimilate crude facts 

 and render them digestible. Details not 

 bearing directly on the subject should be 

 carefully excluded. Most original papers 

 could be " boiled down " to one half and 

 some even to one tenth of the amount that 

 is really published. The effect of the work 

 of the naturalist upon his own character is 

 best shown by his optimism. One drawback 

 in the naturalist's life is his comparative 

 loneliness and isolation. Seldom has he in 

 his own neighborhood another interested in 

 the same particular line as himself. Reunions 

 of naturalist societies counteract this to a 

 considerable extent, but there is need of even 

 greater affiliation. Naturalists should exer- 

 cise influence in teaching men competence. 

 The solution of our present political troubles 

 lies not so much in restricting the right to 

 vote as it does in restricting the right to be 

 a candidate. We, as naturalists and as citi- 

 zens, should uphold competence. The natu- 

 ralist should see that the schools educate, 

 with science in its proper place. 



The Senses of Plants, The conclusion is 

 reached by J. C. Arthur in a president's ad- 

 dress before the Indiana Academy of Science 

 on The Special Senses of Plants, that plants 

 seem to react sensitively to gravity, light, 

 moisture, heat, and contact. Each is a spe- 

 cial kind of sensitiveness having its own 

 method of reaction. Two or more kinds of 

 sensitiveness may reside in the same organ, 

 when its position will be a resultant of the 

 several forces. There are consequently no 

 exclusive organs of sense, although there is 

 more or less localization in certain parts, and 

 there are no nerves, although the motor im- 

 pulse may be transmitted some distance, even 

 so far as twenty inches or more in very vigor- 

 ous Sensitive Plants that is, in Mimosa. 

 There are also no muscles in plants, although 

 they execute movements of very consider- 

 able amplitude. The real mechanism by 



which the movements are accomplished is 

 not well understood. There is agreement, 

 however, in assuming it to be due to the 

 movement of water. All the senses, except 

 that of contact, have for their end the ad. 

 justment of the plant as a whole, and of each 

 of its organs, in a suitable position for heat 

 development. The contact sense has been 

 more variably developed, aiding the plant to 

 climb, to catch insects for food, and, if we 

 are to accept Darwin's suggestion, enabling 

 the Sensitive Plant in particular to escape 

 the injury of hailstones. All the movements 

 are very slow, except a few like insect-catch- 

 ing and hail-avoiding movements, and their 

 wonderful diversity and extent are realized 

 only by instituting carefully devised experi- 

 ments and the use of delicate instruments. 

 It is to be noted that the same organ always 

 responds to the same stimulus with the same 

 corresponding movement. There is no op- 

 portunity for choice, no volition, and conse- 

 quently no mental activity, no psychic life of 

 even the most humble and rudimentary na- 

 ture. 



Characteristies of Maps. Maps, said Dr. 

 R. H. Mill, in a lecture on Holiday Geography 

 at the Royal Geographical Society's rooms, 

 may be viewed as a kind of shorthand, and 

 are easier to read than books. Far more in- 

 formation is given in a map than could be 

 written or printed upon a piece of paper of 

 equal size, and a map could point out to sev- 

 eral persons coming from different direc- 

 tions the way to a certain place, since it does 

 not introduce the confusing notices of right 

 and left, as verbal instructions do. In Aber- 

 deen the confusion is avoided, because there 

 a man is told to go north or south instead of 

 to the right or left ; and it is even said 

 that in some places in Scotland the position 

 of the dishes on the table is regulated by the 

 same principle. The value of maps depends 

 on their purpose and their accuracy. A map 

 that had been taken from a tramp, exhibited 

 to the audience, though worthless for the 

 measurement of distances, was very valuable 

 to the beggar, since all the houses were 

 marked upon it, and the character of their 

 inhabitants, together with the presence of 

 dogs, were indicated by peculiar signs. In 

 a number of old pictorial maps various 

 strange animals were seen disporting them- 



