IDENTIFICATION OF EUCAXYPTS. 91 



often of the same color and one edge of the leaf being turned upward and the other 

 toward the ground; much less frequently considerably darker above and spreading 

 horizontally; oil dots pellucid or concealed; peculiarly and strongly odorous; primary 

 veins often numerous and much spreading. Inflorescence either axillary or terminal, 

 or more rarely both modes united; flowers in single or paniculated umbels, rarely in 

 twos, or solitary; umbel stalks and flower stalklets commonly present, the former 

 sometimes much dilated; umbels while very young inclosed in a pair of fugacious and 

 sometimes diminutive bracts; calyx very variable in size; lid often provided with a 

 minute early deciduous accessory outer layer. 



Calyx of firm texture and separated into a lower persistent portion and a deciduous 

 lid. Petals none, unless represented in some few species by an inner membrane. 

 Stamens very numerous, inserted close to the edge of the calyx tube in several rows, 

 all fertile or some of the outer by absence of anthers sterile, always finally deciduous; 

 filaments thread-like, pointed, inflexed while in bud, or the outer or very seldom 

 all filaments straight before expansion; anthers dorsified, their two cells parallel or 

 divergent, each opening by a marginal or anterior slit or less commonly by a pore. 

 Style long; stigma convex or almost flat, undivided, seldom much dilated beyond 

 the summit of the style. Ovary 2- to 6-celled, its lower portion grown to the calyx, 

 its upper portion more or less free. Ovules in each cell numerous, the majority 

 remaining unfertilized. Cotyledons broad, much compressed, somewhat folded, 

 undivided or 2-lobed, curved around the cylindrical straight, erect radicle. Fruits 

 for a long while persistent, form very small in some species to remarkably large in 

 others, oftener smooth than streaked or ridged, valves always glabrous, very rarely 

 permanently connected by the persistent base of the style. Seeds long retained in 

 the persistent fruit, but soon shed on detachment of the latter; fertile seeds usually 

 outside, dark brown; sterile seeds mostly pale brown and smaller than the others. 



DETERMINATION OF SPECIES. 



To identify the species of so large a genus is a difficult task. The 

 system of identification adopted below is based on the structure of the 

 anthers, the position of the valves, the shape of the lid, the form of 

 inflorescence, and the similarity or dissimilarity of the two leaf sur- 

 faces. The first thing to ascertain about a Eucalypt that one wishes 

 to identify by the use of the key below is the structure of the anthers. 

 This can usually be done with a good lens by examining anthers from 

 buds just ready to open. In using the key. the second thing to ascer- 

 tain is whether the valves of a mature seed case arc inclosed within it 

 or project partly or wholly from the mouth. It is hoped that the 

 accompanying plates will aid in the work of identification. (Pis. XC 



andXCI.) 



It must be understood that all specimens will not plainly fall into 

 any particular subdivision of the genus, and can not therefore be 

 readily identified, especially by a beginner. But with a little patience 

 and wider experience it will be found that most trees can be identified 

 by the use of the keys and reference to the descriptions and illustra- 

 tions. When a specimen has been traced to the species to which it is 

 thought to belong, it should be ascertained if the species has been 

 treated in detail earlier in the publication. If so. reference to the 

 description and to the illustrations of the species in question will aid 



