A HISTORY OF THE SPECIES OF CROCUS. 



253 



the several species, is more easily distinguished by the eye than 

 described. The seed should be sown in the autumn ; if kept too 

 long dry, it will not sprout the first season. 



It might have been expected that a genus which branches into 

 so many local species and local varieties, with a great uniformity 

 of floral structure and of habit, would readily yield cross-bred 

 intermixtures in cultivation. The reverse is the case. Irida- 

 ceous plants in general cross unwillingly, if at all ; but the im- 

 pediment seems almost insurmountable in Crocus. The pollen 

 is very readily and early cast. It requires therefore some skill 

 and care to take out the anthers with a sharp pair of tweezers 

 before the pollen touches the stigma ; but, when that has been 

 done, and the pollen of a kindred species applied, the usual re- 

 sult is no seed. I have tried many years, and I cannot assert 

 that I have yet succeeded in obtaining a cross, though I have a 

 few seedlings and a few seed-pods which must be cross-bred, if 

 no natural pollen eluded my caution. I have found that although 

 C. vernus ripens its seed and sows itself so as to be a nuisance 

 in my garden, if a plant is taken up and potted while in flower, 

 the flowers which had previously expanded make seed, but those 

 which are produced afterwards never do so. I find C. vernus 

 unwilling to make seed at all or even to flower freely, if kept in 

 a pot, though plunged in sand. On its native mountains the 

 flower often pierces the snow, and the crown of the bulb must 

 be colder than the underground fibres. In a pot the reverse is 

 the case, the bulb being probably warmer and wetter than the 

 fibres. I apprehend that the relative degree of warmth and 

 moisture which the crown of a root and its lower fibres enjoy 

 may be very important in the mystery of cultivation and the fer- 

 tility of plants. 



It is observable that autumnal Croci, which have been kept 

 dry and out of the ground beyond their usual time, are very apt 

 to push the flower immediately after they are planted, although 

 in due course the leaves might have been disposed to push first. 

 That habit may therefore have been perhaps acquired by different 

 species in consequence of the amount of autumnal moisture and 

 the time of its usual occurrence. I should imagine that the habit 

 of flowering in the spring will be prevalent where the vicissitude 

 of heat and drought is least felt ; the autumnal habit, where it is 

 most decisive. In order to flower the later autumnal species, 

 such as C. serotinus, early in our climate and during the sunny 

 days, the bulbs should be taken up as soon as the leaves decay, 

 dried, and replanted in about a month ; and if the month of 

 August is very dry, they may be excited to prepare for early 

 flowering by watering them. The rarer sorts which are in- 

 tended for the room or conservatory should be potted, perhaps 



