128 THE SURVIVAL OP THE UNLIKE. [iV. 



types, or that, independently of origin, they merit 

 specific recognition. The chief author who takes the 

 latter view is Sturtevant, who, whilst accepting the 

 common origin of all types of maize, nevertheless pre- 

 fei-s to recognize seven "agricultural species," as 

 follows: Zea tmiicata, "a primitive form," from which 

 the other six are derived; Zea everta, pop corns; Z. in- 

 durata, flint corns; Z. indentata, dent corns; Z. amylacea, 

 soft corns; Z. saccharata, sweet corns; Z. amylea-saccha- 

 rata, the starchy -sweet corns. Whilst these species are 

 not accepted by the regular botanists, there can be no 

 doubt that some of them would be regarded as distinct 

 species if they should turn up in an evidently wild 

 state; and a proof of this statement is found in Wat- 

 son's Zea canina, which was founded upon wild corn 

 collected in southern Mexico. Now, Mr. Watson was 

 one of our most conservative American botanists, and 

 any new species which he should describe could be 

 depended upon to have good botanical characters; yet 

 this new Zea canina is so like our rice pop corns that 

 Sturtevant unhesitatingly refers it to his Zea everta, thus 

 showing that it is not more unlike ordinary corn than 

 some types of pop corn are! Moreover, this corn is 

 found to lose quickly the very botanical characters upon 

 which the species is founded, when it is brought into 



Herbarium, refers Miller's Lycoperaicum pimpinellifolium, to L. Humholdtii (see 

 DC. Prodr. xiii. i. p. 25). Martyn's edition of Miller, 1807, however, refers it back 

 to /So?rtn»<m, and writes of it as follows: "Habit and stnicture of S. Lycopersi- 

 cum. Fniit liko that of its variety B [Clierry tomato]. But it differs altogether 

 from .s. Lji'i^j'i-rsicum in having the stem smooth, without any hairs scattered over 

 that or tho peduncles, the leaves smooth entire cordate, not at all gashed or 

 toothed as in that. However it agrees upon the whole in structure, it may per- 

 haps come from that. The structure of the peduncles is the same as in tuheromm, 

 Lycopersiciim and perucianum, with the pedicles also jointed, and the raceme 

 paked, as in the two former, not leafy as in the la?t." 



