230 XXXVII. MYKTACEiE. [Eucalyptus. 



Obdee XXXVII. MTRTACE^. 



Trees or shrulDs, with simple, generally entire leaves, in most genera 

 dotted with translucent glands, opposite or alternate, without stipules. 

 Flowers regular and generally bisexual. Calyx-tuhe adnate to the ovary, 

 Umb free, 4 - 5 - cleft, often closed iu bud, and bursting into irregular 

 lobes, or coming off entire. Disc coating the calyx-tube. Petals 4-5, 

 sometimes none, inserted on the edge of the disc, in bud imbricate, some- 

 times more or less connate into a caducous calyptra. Stamens perigynous, 

 generally numerous, inserted on or inside the edge of the disc, in one or 

 several rows ; filaments free, or connate at the base in a short ring or tube, 

 or in bundles generally opposite the petals ; anthers 2-celled, versatile or 

 basifixed, the cells mostly dehiscing longitudinally. Ovary syncarpous, 

 inferior, rarely adnate at the base only, either 1 -celled, or more often with 

 2 or more cells ; style simple ; stigma small, capitate or peltate ; ovules 

 numerous. Seeds generally without albumen. — Gen. PI. i. 690 ; Eoyle 

 lU. 216 ; Wight lU. ii. 6. 



Leaves dotted with resinous glands, generally opposite. 

 Calyx truncate, the orifice closed by a deciduous operculum ; 

 fruit hard and woody ; leaves of young shoots opposite, 

 of flowering branches alternate . . . .1. Eucalyptus. 



Calyx generally lobed ; leaves opposite ; fruit fleshy. 

 Free portion of calyx entire, bursting irregularly or coming 



off entire . . . . . : 2. Psidium. 



Free portion of calyx 4-5-lobed . . . .3. Euobnia. 



Leaves not dotted with resinous glands, alternate. 

 All stamens antheriferous ; fruit dry . . .4. Baerinqtonia. 



A portion of stamens only antheriferous ; fruit fleshy . 5. Careta. 



1. EUCALYPTUS, L'ffiritier. 



Shrubs or trees attaining sometimes a gigantic size, secreting more or 

 less of resinous gums, whence their common appellation of " Gum-trees ; " 

 often flowering when quite young and small. Leaves in young saplings 

 generally horizontal, opposite, sessile, and cordate; in the adult tree 

 mostly vertical, alternate, petiolate, and passing more or less from broadly 

 ovate to lanceolate, acuminate, and falcate, always rigid. Plowers in 

 umbels or heads, usually pedunculate. Calyx-tube adnate to the ovary, 

 truncate, the orifice closed by an operculum (formed of the concrete petals 

 and calyx-lobes?), generally thick, fleshy or woody, covering the stamens 

 in the bud, and filing off entire when the stamens expand. Stamens 

 numerous, in several series. Ovary inferior, the summit glabrous, flat 

 convex or conical, 3-6-celled, with numerous ovules in each cell, on an 

 axile placenta. Fruit consisting of the more or less enlarged truncate 

 calyx-tube, usually of a hard and woody texture, interspersed with resin- 

 ous receptacles. The fertile seeds are often, but not in all species minute ; 

 the embryo has broad-cordate 2-lobed or bipartite cotyledons folded over 

 the straight radicle, but otherwise flat. A large proportion of the seeds 



