HYBRID NICOTIANAS. 



25$ 



same cross was made at Verrieres, in 1901, and I can report only the results 

 of the first generation, which are very different from Mr. Daveau's hybrid: 

 Plants very strong and high (2 m. 50), general appearance of some of the 

 varieties of N. tabacum used for tobacco making, flowers with a long tube 

 (6 cm.) small and pointed petals, pale rose, forming a loose panicle; the 

 flowers and are thus intermediate between those of the N. sylvestris and N. 

 tabacum. Seems to give seeds. 



FIFTH CASE: N. tabacum (very deep red variety) and N. affinis. Cross 

 made in 1899, gave a plant very like N. affinis in general bearing and shape 

 of flowers, but dwarfer and not so strong. The flowers are smaller and a 

 little shorter, sometimes (on the same plant) pure white, sometimes rose on 

 the outside and white inside, sometimes rose or varigated in the inside. This 

 very interesting hybrid is unfortunately absolutely sterile ; all attempts at 

 self-fertilizing or crossing with other varieties or species were complete fail- 

 ures. Since 1900 it has been propagated by root cuttings. 



SIXTH CASE: Nicotiana glauca and N. tabacum. Cross made in 1901. 

 Tn 1902 gave two forms : 



A. 11 plants (out of 12), quite like one another, tall (2 m.), 

 branched, leaves oval ; flowers small, greenish yellow when young 

 and afterwards rose ; these plants are evident hybrids. More closely 

 related to N. tabacum than to N. glauca. 



B. The twelfth plant quite distinct, 80 cm. high, flowers very 

 short, petals rounded, yellowish green, seeds abundant. That plant 

 is different from the eleven others resulting from the same cross and 

 also from both parents, which fact it is very difficult to account for, 

 especially in the first generation. 



This last hybridization was made solely as an experiment, there being 

 no chance of improving N. tabacum by a cross with N. glauca. 



CONCLUSIONS. 



(1) In all cases first generations have been very infertile, giving only 

 a few seeds from late flowers, except in case 5 where the hybrid is completely 

 sterile and in the form B of case G where the hybrid is very fertile. 



(2) In some cases the plants of the first generation are intermediate be- 

 tween the parents and entirely like one another except in case 1 wherein was 

 noticed a slight retrogression towards the mother and again in case G wherein 

 the form B is very distinct from both parents. 



(3) The first generation hybrids were more closely related to the 

 mother than to the father in case 4 and the reverse in cases 1, 2, 3, 5 and 6, 

 but in cases 1 and 2, where the second and third generations were observed 

 there is a distinct retrogression towards the mother. 



(4) Generally the hybrids are neither so tall nor so strong as their 

 parents, but, because of their sterility, have a splendid and long enduring 

 inflorescence. 



I acknowledge that these conclusions are vague and unsatisfactory, but 

 I must be content with them for the present. I hope that further experiments 

 may help to a true knowledge of the transmission of characters in hybrids. 



