4 BOTANICAL GAZETTE [january 



case of O. deserens, as previously mentioned, and since then it has 

 been studied carefully in this respect. 



After repeated cultures of pure O. deserens had been made and 

 compared with O. rubrinervis , the characteristic marks of the two 

 forms became quite clear and reliable, although very small. In 

 mixed cultures the types may even be separated when very young, 

 but some dubious specimens may remain. At the time of flowering 

 these have almost always been shown to belong to the new type. 

 Among the very young rosettes, with only 3-5 leaves, those of 

 deserens are broader and more flattened and of a deeper and purer 

 green, resembling therein young plants of 0. Lamarckiana. These 

 differences increase slowly until the time when the rosettes must 

 be planted out from the boxes into the garden, about the middle 

 of April. The leaves of O. deserens have now a broader base and 

 a less pointed top than those of 0. rubrinervis, besides the marks 

 already given. In July the differences remain very small, the two 

 types reaching the same height at the same period, but the rubriner- 

 vis begin to flower one or two weeks earlier than the deserens. Seen 

 from above, the spikes show narrow, folded bracts in the first type 

 and flat, broad ones in the second type. This character is easily 

 appreciated and wholly reliable; no dubious cases trouble the 

 counting in mixed cultures. The beginning of August, when the 

 deserens have opened only a few of their first flowers, is the best 

 time to separate them. A difference in the color has now become 

 clear, the red tinge of the parent type failing in the deserens. Here 

 the leaves, bracts, and flower buds are green, and the flowers are 

 also of a purer yellow. A number of smaller marks, which are 

 helpful in the distinction, almost escape description, as, for example, 

 the form of the flowers, their grouping at the top of the spike, and 

 the more erect position of the buds before opening. 



The main character of 0. rubrinervis is the brittleness of all its 

 parts, as already mentioned. It is exactly the same in 0. deserens. 

 I have broken the stems of all the plants to be mentioned in this 

 article at the time of sorting them out in August or after harvesting 

 their seeds, but no exception has been found to this rule.'' Hybrids 



-t I have, moreover, injected all the seeds for the sowings of the later years under 

 a pressure of 8 atmospheres during 48 hours, this being the only reliable means of 

 making the germination as complete as possible. 



