May 22, 1914] 



SCIENCE 



741 



cuiTent, for they could not be reconciled 

 with the known facts and therefore were 

 disregarded. ' ' 



The obligation to be efficient in the avoid- 

 ance of error is by no means to be taken 

 lightly. The young writer who excused 

 his carelessness of statement and inaccu- 

 racy of citation by saying "everybody 

 makes mistakes" no doubt uttered a truism, 

 but he also displayed his profound igno- 

 rance of the difficulty with which a mis- 

 statement is rectified when once it has 

 gained a footing in literature. There is 

 perhaps no more striking example of the 

 strange fabric that may be woven with the 

 w-arp of truth and the weft of oversight 

 or error, than the biological principle 

 known as Von Baer's law. 



Von Baer is renowned as the originator 

 of the theory that the embryo of every 

 higher animal during its development 

 passes through successive stages in which 

 it simulates the advilt forms of the lower 

 animals in the same phylogenetic series. 

 But Von Baer did not originate this theory, 

 indeed he was its most vigorous opponent. 

 Wliat he really taught was that the embryos 

 of different animals are similar to each 

 other in that they adhere to the same plan 

 of development, but through the failure 

 of some of his contemporaries to be precise 

 and discriminating, the ideas of another 

 man were mistaken for those of Von Baer, 

 and the latter was thereby placed in a 

 false light in respect to the contribution 

 which he made to science. 



Manifestly a high degree of efficiency is 

 just as desirable in interpreting and citing 

 the writings of other workers, as it is neces- 

 sa-ry in planning and successfully conduct- 

 ing the work of experimentation, and the 

 scientific worker who renders the best 

 service both to himself and to his science 

 -*ill be as zealous in avoiding the perpetua- 



tion of error as he is ardent in his search 

 for truth. 



It is a social obligation of the botanist to 

 strive for a better organization of his sci- 

 ence. It is not my intention to raise that 

 much-discussed question "What is bot- 

 any?" the answers to which are approxi- 

 mately as numerous as those who are or 

 who think themselves botanists, although I 

 deprecate the contrariety of opinion which 

 exists with respect to what may properly 

 be included in the domain of this science. 

 Some maintain the old distinction between 

 pure and applied science, and would ex- 

 clude from the science of botanj' such sub- 

 jects as plant breeding, economic botany 

 and plant pathology; others think botany 

 is largely an applied science, consisting in 

 part of mere applications of other sciences ; 

 some conceive the science as largely re- 

 stricted to one of its phases, as, taxonomy, 

 morphology or physiology ; and still others 

 maintain that botany is not a single science 

 but a group of distinct sciences with noth- 

 ing in common except the fact that they 

 are concerned with the phenomena pre- 

 sented by plants. 



Segregation and specialization in vari- 

 ous lines of botanical activity seem to be 

 a natural process necessarily attendant 

 upon scientific progress. Competition be- 

 tween these lines, each of which seeks to 

 gain the ascendency, and to become recog- 

 nized as the true representative of the 

 science, also seems not only natural, but 

 necessary to normal and progressive devel- 

 opment. There exists, however, a suffi- 

 ciently close analogy between the evolution 

 of a science and certain phases of organic 

 development to justify the consideration 

 of a well-established biological principle in 

 discussions of the relative importance of 

 different branches of the science, or the 

 promise which they hold out of contrib- 

 uting most to its advancement. This prin- 



