248 



PHILOSOPHICAL NOTES ON 



Fig. 94. Petiolar vessels. B. bud ; F. leaf scar ; F.V. fibro.-vasc. bundle.* 



off-sets from the bark. It is obvious that the possible or actual 

 formation of a bud in the axil of each leaf is favoured by the 

 presence of vascular tissue." 



At p. 33, he says, " Spiral vessels may be few (in Oryptoga;n«), 

 but there are phsenogams of very tKfferent aspects and affinities, in 

 which they are equally or more deficient." 



I have endeavoured to show that the presence of the axillary 

 bud is not due to vascular tissue in the vicinity of the axilla.- 

 Whatever gave origin to the vascular tissue in the leaf at all 

 must have given origin to that of the axillairy bud also, as a: 

 branchlet or sub-division of the leaf, which eventually coalesced 

 with the stem and remained as part of the . stem, and is now 

 designated axillary bud ; while the rest of the leaf became 

 deciduous and was thrown off after decay. 



The sporangia of Selaginella incequalifolia^ are no other 

 than the branchlets of the modified leaves of the spike. They, are 

 not connate, either with the stem or with the petiole. 



In Isoetes lacitstrisX the sporangium (also a branchlet of the 

 leaf) becomes connate and einbedded in the base of the leaf. 

 While in phasnogams the axillary bud (also a branchlet. of the 

 leaf) becomes connate "with the stem, the leaf proper becoming 

 deciduous. 



* Fig. 696, Le Maout and Decaisne. 



t " Goebel's Outlines of Classif.," p. 292. 



+ 5> » » P- •<i95. 



