A STUDY IN PLANT VARIATION 233 



and not so pointed as those of the common plumb; smooth and of a 

 shining green on the upper surface, but something Hghter underneath,, 

 and sHghtly sawed on the edges. It is generally well filled with flowers^ 

 a few of which are succeeded by small, roundish fruit. " 



The authorit>' usually given as the first describer is Wangenheim 

 (31, p. 103) in 1781. A copy of this work from the Academy of Natural 

 Sciences of Philadelphia was carefully searched but no record of Prunus 

 maritima was found. In another work {il, p. 103) published in 1787, 

 Wangenheim describes this species. Through some error in the dates 

 of these publications, which has been passed on without investigation, 

 it seems that Marshall (19, p. 112) has never been given credit for what 

 he truly deserves, namely — the original describer of P. maritima. On 

 the title page of Wangenheim (31) I found that he served as a captain 

 in the Hessian Army during the Revolutionary War from 1777-1780. 

 According to Stone (27, p. 491) this specimen which Wangenheim des- 

 scribed came from Long Island, N. Y. In view of these facts, and since 

 there is no mention of the name of the collector given by Stone (27), 

 at the above named place, it seems probable that he saw this plant, 

 while in the army service, and upon his subsequent return to Germany 

 published what has been considered the original description.^ 



Loudon (17, p. 691) described it as a native of North America; intro- 

 duced into Europe in 1818, and, while it produces blossoms there in 

 great abundance, yet he is not aware of any producing ripened fruits. 

 In America, according to Pursh (22, p. 332), they are succeeded by fruit, 

 of the size of a pigeon's egg, dark purple and very good to eat. 



Until 1825, Prunus marilima was described under various synonyms. 

 Beck (2, p. 95) points out the similarity of descriptions among certain 

 species, yet suggests that they may be distinct. Torrey (29, p. 194-5) 

 and Torrey and Gray (30, p. 408) confirm Beck's suggestion and give 

 a list of some of the synonyms used. 



Prunus cerasi^era 

 Prunus acuminata 

 Prunus sphaerocarpa 

 Prunus pygmaea 

 Prunus pubescens 

 Prunus littoralis 



All these are now grouped, however, into the one species — now under 

 consideration. ' 



1 Since the above was written, Wight {Si, page 55) in a recent publication, 

 dated April 2, 1915, arrived at the same conclusion. 



