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species of the ephemerals, but my opinion is that the number 

 of individuals of most of the ephemeral species is much 

 larger than that of the summer-annuals. This question ought 

 to be more closely investigated. 



Even though the adaptations of the summer -annual 

 plants must be regarded as favourable, otherwise the plants 

 would not be able to exist, they seem to be much less 

 favourable than the adaptations of the ephemerals or those 

 of the perennials. The latter remain alive year after year, 

 capable of storing nutriment and of developing a stiong 

 root-system, while as regards propagation by seeds they have 

 the same chance as the annual plants. 



The annualness of the annual summer-plants inherent 

 in their nature thus seems to be an unfavourable point in 

 their adaptation to the conditions of the Transcaspian desert. 

 That so few species of them occur there is perhaps a result 

 of this. 



Next to the Therophytes the Hemicryptophytes are 

 the most abundant type in the Transcaspian desert. Their 

 percentage (27) ranges between the figures from the North- 

 African and North- American desert (19, 20, 18) and Samos 

 (32) as shown in Table 3. They are far less numerous here 

 than in the South-Russian steppe (Yekaterinoslaw) and Pamir. 



Most of them flower early, about the month of May. 

 After calculation, I find that only about 10 per ct. of the 

 Hemicryptophytes flower after July 1, so that about 90 per 

 ct. are early flowering. These figures are only approximate, 

 as details on the flowering season of many species are 

 lacking. 



Actual numbers have less interest here than in the case 

 of annual plants, because the latter usually die after they 

 have produced flower and fruit, whereas perennial plants in 

 many cases continue to be vegetative after that time. Statis- 

 tics of the flowering season therefore give no information 

 about the vegetative period of perennials. 



Most Hemicryptophytes flower early and have completed 

 flowering before the end of June. As previously stated (p. 59) 

 many of them wither when the seeds are ripe. This is 

 probably the case with the majority, some of them have 



