Makch 29, 1918] 



SCIENCE 



307 



and yet I have made no careful search. Bo- 

 tanical literature is fuU of cultigens, improp- 

 erly or incompletely coordinated into taxo- 

 nomic treatment. 



The prime deficiency is the fact that many 

 of the good cultigens are unrecognized botan- 

 ically. In the presimied manual of cultivated 

 plants, how would the author treat the tuber- 

 ous begonia? "Would he enter descriptions of 

 the several indigenous species from which the 

 cultigenous group has come, and stop there? 

 But what, then, would the horticulturist do? 

 He would say that Begonia Veitchii, B. rosce- 

 flora, B. Davisii, B. Pearcei, B. Clarkei are 

 not in cultivation so far as he knows, and he 

 asks what he shall call the tuberous begonia. 

 He would charge that the tuberous begonia is 

 left out, and his statement would be correct. 

 If he is a dealer, he naturally and properly 

 wants a name in his catalogue comparable with 

 Begonia Rex and B. semperflorens. Voss solves 

 this problem by calling the cultivated group 

 B. tuberhyhrida. 



Now the botanist will say that Begonia tu- 

 ierhyhrida has no " type," no clear description 

 properly published, and therefore no rec- 

 ognized taxonomic standing. It is essentially 

 as good a case, however (except traditionally), 

 as Zea Mays, which some persons now con- 

 sider to be a bigeneric hybrid. 



If we accept the Linnean and other historic 

 cultigens, why not accept modern groups of 

 similar or comparable origins? Are the fol- 

 lowing "good species" in the strict sense? 

 Triticum vulgare L., Hordeum vulgare L., 

 Secale cereale L., Helianthus annuus L., Sac- 

 charum officinarum L., Pyrus Malus L., 

 Ipomoea Batatas Poir., Aiutilon pleniflorum 

 "N. E. Br., Lonicera americana Koch, Lilium 

 japonicum Thunb. and L. testaceum Lindl., 

 and any number more. We have similar 

 cases in the domestic animals, as Felis domes- 

 tica, Gallus domesticus, Canis familiaris. 



What are we to do with cultivated black- 

 berries, Lxias, gladiolus, fuchsias, and many of 

 the magnolias, deutzias, spireas, pandanus, 

 roses 1 What are we to do with the cultivated 

 canna: what is this plant? Are we merely to 

 pass it by, undescribed because it is a com- 



plex? To describe the various species of 

 canna is of no consequence to its identifica- 

 tion. At present there is no name under 

 which we can describe the common garden 

 canna. The point is, are we to name and 

 describe cultivated plants or are we not? 



What are we to do with such things as 

 Saintpaulia hewen-sis, Tritonia crocosmwflora. 

 Iris flavescens, Ligustrum coriaceum, Eryn- 

 gium Oliverianum, Fuchsia speciosa, Heuch- 

 era brizoides, Primula Polyantha? 



The cultigens are with us, and the numbers 

 win increase. Ko longer can we let them go 

 by default. The plant-breeder will bring his 

 new groups ; will taxonomy expand itself to 

 receive them, or must they always be outcasts ? 



Even when the parent indigen is known, 

 many of these cultigens have their own entity 

 and by every taxonomic right should be sepa- 

 rately recognized. They often present char- 

 acters new, or different from those of the 

 fundamental species, or at least in different 

 combination. When recognized as admissible 

 gentes, in the company of living things, 

 they are no longer involved in debates as to 

 the taxonomic merits of their ancestors. Even 

 if we were satisfied to say that the cultivated 

 blackberries are Euhvs allegheniensis, what 

 are we to say when B. allegheniensis is itself 

 split into a dozen segregates? 



Supose, now, we are to agree that 

 Zea Mays is a hybrid of Euchlwna mexicana 

 and X : are we then to describe E. mexicana 

 and X in our manuals, and to say that Indian 

 com is a hybrid between them, dropping the 

 name Zea Mays entirely ? This is exactly the 

 type of treatment we are giving great numbers 

 of cultigens that have well-marked character- 

 istics of their own. Many of our common 

 cultivated plants can not be put in our man- 

 uals, because we have no names to call them 

 by. What are we to call the florist's chry- 

 santhemum? To describe its supposed par- 

 ents, C. indicum and C. morifolium, is of no 

 consequence; these are unknown to the culti- 

 vator, and moreover they are not the florist's 

 chrysanthemum. 



It is said that to admit such forms into the 

 society of recognized species would greatly 



