RUTALES.] 



AURANTIACEiE. 



457 



Order CLXX. AURANTIACE^.—Citronworts. 



^--^antiacese, Corr. Ann. Mus. 6. 37fi. (1805) ; Mirb. Bull. Philom. 379. (1813) ; DC. Prodr. 1. 536. 

 (1824) ; Endl. Gen. ccxxiv. ; Wight Illustr. 1. t. 42. 



Diagnosis. — JRiital Exogcns, toith consolidated succident indeJiiscent fruit, imlricatcd 

 petals, free or nearly free stamens, and dotted leaves. 



Trees or slirubs, almost always smooth, and filled everywhere with Uttle transparent 

 receptacles of volatile oil. Leaves alternate, often compound, 

 always articulated with the petiole, which is frequently winged. 

 Spines, if present, axillai'y. Calyx m'ceolate or campanulate, some- 

 what adliering to the disk, short, 3- or 5-toothed, withering. Petals 

 3 to 5, broad at the base, sometimes distinct, sometimes slightly 

 combined, insei*ted upon the outside of an hypog^Tious disk, slightly 

 imbricated at the edges. Stamens equal in number to the petals, or 

 t-vvice as many, or some multiple of their number, inserted upon the 

 same hypogynous disk ; filaments 

 flattened at the base, sometimes 

 distinct, sometimes shghtly com- 

 bmed in one or several parcels ; 

 anthers termmal, innate. Ovary 

 free, many-celled ; style 1, t^per ; 

 stigma shghtly divided, thickish ; 

 ovules solitary, twin, or 00, pendu- 

 lous or occasionally honzoutal, ana- 

 tropal. Fniit pulpy, one or more- 

 celled, sometimes with a leathery 

 rind replete with receptacles of 

 volatile oil, and even separable 

 from the cells ; cells often filled 

 with pulp. Seeds attached to the 

 axis, sometimes numerous, some- 

 times sohtary, usually pendulous, 

 occasionally containing more em- 

 bryos than one ; raphe and chalaza 

 usually very distinctly marked; albu- 

 men ; embryo straight ; cotyledons 

 thick, fleshy ; radicle very short. 



These are readily known by the abundance of oily receptacles which are dispersed 

 over all parts of them, by their de- 

 ciduous petals, compound leaves, 

 often with a winged petiole, im- 

 bricated petals, and succulent or 

 pulpy fruit. They are nearly 

 related to Amends on the one 

 hand, and to various genera of 

 Rueworts on the other, but differ 

 from the first in theu' pulpy 

 finiit and imbricated petals, and 

 from the latter in their consoli- 

 dated juicy fruit. It is more 

 difficult to distinguish them from 

 Xanthoxyls, imless attention is 



paid to the fruit, the apocarpous . ^^^^.^^ 



structm-e of the ovary, and the ^'^' <^CC-^I-^- 



polygamous flowers. Luvmiga is I'emarkable for ha\dng the 

 climbing habit of Xanthoxyls, and the fruit of Citronworts. 

 The raphe and chalaza are usually distinctly marked upoia the 

 testa, and sometimes beautifully. The genus Citi'us is very 

 subject to a monstrous separation of the carpels, which produces 

 what are called horned Oranges, and fingered Citrons, the last 

 of which is the genus SarcodactyUs of the younger Gsertner 

 (t. clxxxv.), or to a multiplication of the normal number of 



Fig. CCCXVII. 



carpels, in which case Orange is formed withm Orange. 



Fig.CCCXVlU. 



Fig. CCCXVII.— Micromelum monophyllum.— I^^:J/^^ 1. a flower; 2. the pistU when the calyx is 

 rolled back ; 3. a cross section of an ovary ; 4. longitudinal section of a seed. 

 Fig. CCCXVIII.— A young Orange, with a row of supernumerary carpels. 

 Fig. CCCXIX.— The fruit produced bv this. 



