The Mutations in the Lamarckiana-family. 239 



and had therefore at least three generations of ancestors 

 with the normal high stature. In the same year I also 

 sowed some seed saved from the second generation (1888- 

 1889) and I self-fertilized some of the dwarfs that ap- 

 peared in the crop thus raised. There were altogether 

 20 of them ; they set a quantity of seed from which 2463 

 seedlings were grown. They were without exception 

 0. nanclla. 



Thus we see that every one of the twenty dwarfs which 

 arose spontaneously from O. Lauiarckiana had a perfectly 

 constant progeny. As I have already stated, the plants 

 were not registered as dwarfs until they were strong 

 rosettes and had attained the age of about six weeks. 



I repeated the experiment on a larger scale in the 

 following year, when I had found out how to identify 

 the plants without transplanting them. I used the seeds 

 of nanella plants which had arisen in the fifth generation 

 of the Lamarckiana-isimWy, i. e., plants whose ancestors 

 had therefore been normal for four generations. From 

 the seeds of 36 plants I raised over 18,000 seedlings. 

 These were without exception nanella ; but 3 of them ex- 

 hibited in addition to the dwarf habit the characters of 

 O. ohlonga and constituted an elementary species of the 

 second grade, O. nanella ohlonga. 



Moreover, whenever nanella appeared in other fam- 

 ilies it proved immediately constant, not only in the first 

 but in succeeding generations as well. 



Combinations with other characters occurred in these 

 cultures ; but very rarely. I have often had examples 

 of 0. lota nanella and O. nanella elliptica, and now and 

 again variegated or pitcher forming individuals of 0. 

 nanella, and so on. 



VI. O. lata. This species is solely female: it never 



