ORIGIN OF THE DATE PALM 



Fossils Found in Texas Indicate that it May be Native of America Known Only 



in Orient in Historic Times Its Connection with Semites and Its Religious 



Importance— Influence as Factor of Natural Selection. 



The Editor 



FOR many years botanists have 

 wondered where the date palm 

 as a distinct species originated. 

 Sentiment has seemed to in- 

 cline toward North Africa as its first 

 home, but the precise locality sug- 

 gested has varied all the way from 

 western Morocco to eastern Egypt; 

 while the German botanist Schwein- 

 furth declared his belief that Phoenix 

 spinosa o^. tropical Africa was the 

 species most ncarh- like the ancestral 

 type of date palm, if indeed the latter 

 was not a direct descendant of P. 

 spinosa. The Italian botanist Odoardo 

 Beccari, who is by general consent the 

 authority on palms at present, con- 

 sidered the Persian Gulf to be the home 

 of the date palm, and set forth' his 

 jjosition in such a logical way that the 

 question seemed for a time to be settled. 

 "It is only in the orient," says 

 Beccari, " that the true home of the date 

 palm is to be found ; in the orient where 

 the true center of formation of the 



genus Phoenix is located and where the 

 wild species most closely related to the 

 domestic one — namely, Phoenix syl- 

 vestris — exists." 



Beccari then elaborates his evidence 

 in more detail. The home of the date 

 palm must first be generally fixed by 

 finding the home of its whole genus. 

 The present distribution of Phoenix 

 indicates that this must have been in 

 India, according to Beccari's way of 

 thinking. Next, the home of the date 

 palm must be more definitely located, 

 by a consideration of the physiological 

 and morphological characters of the 

 ])lani. We have a palm which thrives 

 only in subtropical regions with scanty 

 rains, but demands much moisture 

 about its roots, and is remarkably 

 tolerant of alkaline soils. Beccari 

 thinks these facts may be taken to 

 mean that the ancestral home of the 

 date palm possessed similar charac- 

 teristics. He therefore seeks its origin 

 in a region of subtropical climate and 



' Beccari, O. Malosia, III, .vSQ. Firc-nze-Roma, 1886. 



IjlacitiK them under no restraint except that of judicious choice in marriage mating. Tliese rules 

 can Ije summarized as follows: 



"Diseases of parental heredity: individuals who show no traces of the disease should not be the 

 objects of any restrictive measures whatever; nor are consanguineous marriages particularly 

 to be feared. 



"Diseases of matriarchal heredity: descendants of affected males should not be the ()l>jects of 

 any restrictive measures; individuals descending from the common stock exclusively througli 

 the female line may themselves be attacked by the disease, if males, or may transmit tiie disease 

 to male offspring, if females; consanguineous marriages are not ])articularly dangerous. 



"Diseases of fraternal heredity: the malady may lie transmitted in a latent state by all descen- 

 dants oi the affected subjects, or by their collaterals; but its chances of reappearing are much 

 smaller than in the two preceding categories, these first two being of the dominant type. On the 

 other hand consanguineous marriages, no matter Ikjw remote the degree of kinsliip, may be very 

 dangerous in this latter category. As the disease may remain latent tlirough a series of genera- 

 tions, one must go high in the ascendants, far in the collaterals, to be sure that an individual 

 coming from an affected st(jck will marry into an untainted one. In such 'outcrosses,' the chance 

 of a return of the dis;-use becomes very slight." To this I added: 



"In closing, I do not want to slight the fact that application of the rules thus established offers 

 difficulties in many cji.ses. The mode of inheritance has not yet been sulTiciently determined 

 for many family diseases. Some of them seem to fall in two classes. In such cases, it woulil 

 be prudent to double the precautions." 

 498 



