Cockayne. — Development of Seedlings. 83 



Aet. XVI. — An Inquiry into the Seedling Forms of New 

 Zealand Phanerogams and their Developvient. 



By L. Cockayne. 



\_Read before the Philosophical InsUtute of Canterbury, 1st November, 



1S99.] 



Plates Vlir., IX. 



Past III.- 



With regard to the seedlings treated of in my former papers,! 

 it is not worth while making any additions at present to what 

 has been already published. This arises chiefly from the 

 fact that most of the young plants are still growing in the pots 

 where the seed was sown, and, now that spring has returned, the 

 vigorous growth which it has induced, coupled with the moist, 

 sheltered, warm environment of the greenhouse, has brought 

 about in nearly every instance either a reversion to the already 

 described juvenile form, or else that the latter still persists. 

 Thus young Garmichaclia seedlings, which had commenced to 

 develope leafless cladodes, are now putting out leafy shoots ; 

 even adult plants of G. crassicaule, both in greenhouse and 

 shade-house, are rapidly producing stems well furnished with 

 leaves, while on the other hand specimens in the open air pre- 

 sent the usual half-dead looking appearance of the wild plant. 

 Although a greenhouse in spring-time is not good for ob- 

 serving later seedling developments, it does not follow that it 

 is unsuitable for investigating the earlier forms of growth; on 

 the contrary, the conditions of growth there are not so very 

 different from those afforded by nature, since in the natural 

 habitat germination can only possibly take place during a 

 period of wet, when the surface of the ground would remain 

 moist for some time. Ganong writes regarding the Gactaceal : 

 " The germination of the seeds at home in the desert must 

 take place in the rainy reason, for then only is the necessary 

 water available. Now, the conditions of the desert in the 

 cloudy time of the year are not so very different from those 

 of our greenhouses." 



To guard against error in the shape of getting seed- 

 lings wrongly labelled, I have this season adopted the 



* In my former paper, on page 382, line 9, the word seed occurs as a 

 slip of the pen, capsule being, of course, the word intended. I usually 

 sow Veronica -seed capsule and all, especially if the seed be gathered 

 before it is quite ripe. 



t Trans. N.Z. Inst., vol. xxxi., 1898, pp. 354-98. 



\ " Contributions to a Knowledge of the Morphology and Ecology of 

 the Cactacese " (Annals of Botany, 1898, vol. xii., p. 428). 



