208 ECONOMIC BOTANY OF ALABAAIA 



lieved they were perfectly good species, with well-defined tax- 

 onomic and geographical limits ; and it is possible that many of 

 them are ; but the reduction in number of recognized species after 

 1903 seems to indicate that the splitting process had been carried 

 too far. But even in the latest treatments of the genus, which are 

 conservative in comparison with those of 25 years ago, the named 

 forms can hardly be regarded as species in the same sense as most 

 of our pines and oaks, for example. They are probably more 

 nearly analogous to the innumerable horticultural varieties of roses, 

 sweet peas, chrysanthenuims, etc. The distinctions between them 

 are often very finely drawn, depending on such trivial characters 

 as the number of stamens, color of anthers, and slight differences 

 in the shape or color of the fruit. (There is possibly no person 

 living who could name correctly even half of the 153 Crataegus 

 figures in Sargent's Manual if they were removed from the text.) 

 And even if these rather obscure characters were invariable it 

 seems impossible for one wdio does not devote most of his time to 

 this one genus to remember enough of them to identify all the 

 supposed species without a book ; and furthermore, it is necessary 

 to see both flowers and fruit to be sure of the identity of many 

 of the species, and that means visiting the same tree at least twice 

 at intervals of a few months or longer, and makes it impossible 

 to list the species seen on a reconnaissance trip, as can be done with 

 nearly all other trees. 



It is quite likely that many of the supposed species of Cratae- 

 gus, especially those known from only one individual, are hybrids ; 

 but that cannot be proved without breeding experiments, which 

 would take several years for each species. Another possibility is 

 that they have originated by mutation or otherwise in the last 

 hundred years or so. since a large part of the country was cleared 

 up. For a great many of them, as indicated a few pages back, are 

 known only from old fields, pastures, roadsides, etc., which could 

 hardly have existed l)efore the white man came.* 



It happens that the writer has never succeeded in identifying 

 any of the Crataegus forms described in the last 35 years, having 



*See Bull. Torrey Bot. Club 35:354-355. 357. 1908. This question is 

 also discussed or touched upon bv Sargent in Jour. Bot. (London) 45:290. 

 Aug. 1907; H. B. Brown in Bull. Torrey Bot. Club 37:251-260, 1910, and 

 L. M. Standish in Jour. Heredity, June 1916. 



