440 RELATION OF PLANT PHYSIOLOGY TO OTHER SCIENCES. 



but they have considered this question from the ontogenetic standpoint, 

 if I may so express it; they have simply asked. "What conditions of 

 the parents and what influences upon them lead directly to male or to 

 female progeny"? In the above-mentioned work on genealogy the ques- 

 tion is philogenetically treated, if I may thus again express it. The 

 author raises the question, namely, whether inheritance is not of sig- 

 nificance in the determination of sex; whether, to express it plainly, 

 certain fathers or mothers, because of prominent deep-rooted peculiari- 

 ties, are not destined to produce either wholly or chiefly either male 

 or female offspring. 



It is no idle fancy which our historian has brought forward for the 

 statement and proof of this question; on the contrary, with astonish- 

 ment one sees by an examination into this work on genealogy how the 

 author has gone into the finest natural science problems of inheritance, 

 into the subtilest phenomena accompanying creation and the beginning 

 of sex, in order by thus bringing forward in support all available 

 knowledge to give the greater value to his work. 



The genealogical method here brought into use by the author is 

 worthy the high consideration of biologists. He studied the genealog- 

 ical history of numerous families of the nobility and found as a rule 

 that in one, male, in another, female, descendants so predominate that 

 the tendency toward inheritance of sex within a family can scarcely be 

 called in question. 



For further biological studies the following discovery resulting from 

 genealogical investigations ought to be of significance: That in the 

 human family the male element is of more weight in the formation of 

 sex than the female. 



Similarly other branches of knowledge that stand as aids to history 

 e. g., diplomacy and paleography, the same is true also of archaeology, 

 have come to hold certain relations to the natural sciences. The study 

 of the physical characteristics of old documents, of the substance written 

 upon and the material used in writing, was undertaken earlier by the 

 historians themselves. Now, microscopists of various special fields, 

 foremost among them plant physiologists, have taken up this task; they 

 cleared away old errors like the charta bombycina (paper made of cotton 

 which is supposed to have preceded that made of rags), the charta cor- 

 ticina which proved to be papyrus, and many others, and traced the 

 cloth or rag paper, so important to civilization, back to the eighth cen- 

 tury of our era; whereas the historians could trace it only to the four- 

 teenth century, and show that this paper was first invented neither by 

 the Germans nor by the Italians, but was due to the oft illustrated 

 inventive genius of the Arabs. Thus the history of paper was placed 

 by the skillful work of plant physiology upon a new basis whose cer- 

 tainty, tested by the historical researches of the foremost historical and 

 linguistic students, has met with fullest acknowledgment. 



Plant physiology also rendered active assistance in the construction 



