COXIFERALES 



69 



ii 



tion of the structures which can find general application, and 

 yet the groups are so evidently related that any explanation of 

 the ovuliferous structures in one group must apply to all. A 

 brief statement of the principal differences is as follows : 



In the Abieteae there is a small bract, a very much larger 

 and woody ovuliferous scale coalescent with the bract at the very 

 base, and two inverted basal ovules. In the Araucarieae there 

 is a prominent bract, a ligulelike ovuliferous scale (present in 

 Araucarm, wanting in Agathis), and a single imbedded ovule 

 some distance above the base. In the Taxodieae and Cupresseae 

 there is a single bract or scale structure with two distinct apices 

 at the free and enlarged end and bearing one (Juniperus) to 

 many (Cupressus) ovules; in Juniperus this structure becomes 

 fleshy in the or- 

 ganization of the 

 "berry." In the 

 Taxeae there is a 

 single ovule at the 

 end (?) of a short 

 secondary leafy 

 axis, being at- 

 tached to no scale 

 or bract, but be- 

 coming inclosed in 

 seed by a colored 

 and fleshy " aril." 

 In the Podocarpeae (chiefly Podocarpus) there is an " anatro- 

 pous " ovule associated with a bract but carried up far above 

 it on a long stalk, and two integuments (the outer becoming 

 fleshy and colored) ; in some species bracts and axis become fleshy 

 and fuse together " into a colored, succulent whole " (Figs. 44, 

 45, 53-58). 



The chief contention has been in reference to the nature of 

 the ovuliferous (or seminiferous) scale, and in reference to the 

 integument. A very valuable historical study of the subject 

 has been published recently by Worsdell, 47 who has brought 

 together in compact form the principal views which have been 

 held, and to whom we are indebted for much in the following 

 brief account. 



Before 1827, in which year Eobert Brown * announced gym- 



FIG. 54, Finns Laricio, diagram of ovule and associated 

 structures ; J, bract ; s, ovuliferous scale ; f, vascular 

 bundles ; m, micropyle ; *', integument ; />, pollen grains ; 

 c, cavity in apex of nucellus ; , nucellus ; g, embryo sac. 



