1G4 



ROSACEA. Acacia. 



stipules spinescent or iucouspicuous ; flowers small, in glubuse heads oi cylindrical 

 spikes, on axillary peduncles, yellowish. 



A genus of over 400 spi-cics, bulongiiig to the wanner regions of the globe, especially abundant 

 in AustniHu and AlVicii. About a ilozen are iiutivo on the southeru borders ol' the United States, 

 and numerous Austruliau species are heciuent in cultivation. 



1. A. Greggii, (Ji'ay. A small tree 10 to 20 leet high, pubescent with spreading 

 hairs or glabruus, unarmed or with scattered short stout hooked prickles : leaves 

 short, of 2 or 3 pairs of pinnie an inch long : leaflets 4 or 5 pairs, oblong or oblong- 

 obovate, ineiiuilateral, rounded or truncate at the summit, narrower below, 2 or 3 

 linos long, ratiier thick and with 2 or 3 straight nerves : flowers in cylindrical spikes 

 tin indi or two long, tho peduncles (!(|ualling or exceeding the leaves : pods com- 

 l)ressed, curved, 3 or 1 inches lung, f) to 7 lines l)road, attenuate at base to a short 

 stipe and acute above, more or less (umstricted biitwoen the siuuls ; the tbin-coria- 

 ceous valves reticulated: seeds | inch long, elliptical. — PI. Wright, i. 05. 



San Diego {Cleveland) ; San Felipe ('afii)n (Pabmr) ; Fort Mohave {Cooper) ; and eastward to 

 Texas. The species closely resembles A. n'rujhtii, lienth., of the Kio Grande region, which has 

 a broader and obtuser pod, and usually rather larger leaflets. 



A. Faunesiana, Willd. A small spreading tree, witli straight slender stipular spin.s, pubes- 

 cent or glabrous : pinna-. 4 or 5 pairs ; leaflets 10 to '25 pairs, linear, a line or two long, crowded : 

 heads globose : pod oblong, cylindrical, at length turgid and pulpy, 2 or 3 inclies long and 6 to 

 9 lines thick, longitudinally veined. — Widely spread over the subtropical and tropical regions of 

 the New and Old World, and often cultivated for the perfume of its flowers ; native land un- 

 known. About the Missions in the southern part of the State. 



Order XXXI I. ROSACEA. 



Herbs, shrubs, or trees, with alternate leaves, usually evident stipules, perigynous 

 mostly numerous stamens, distinct free pistils from one to many, or in one suborder 

 few and coherent with each other and with the calyx-tubo into a 2 - several-celled 

 inferior ovary, and anatropoua few or solitary seeds destitute of albuuuui or nearly 

 so : these are the characters of this great order. But the stipules are sometimes 

 evident only upon vigorous shoots, and rarely fail altogether, the stamens are some- 

 times even fewer than tho petals or lobes of the calyx, and in a few cases the albu- 

 men of the seed is somewhat copious. — The Californian representatives belong to 

 three great groups, best exhibited as suborders. 



SuuoRDEU 1. AMYGDALE.'E. 



Carpels solitary, or rarely 5, becoming drupes, entirely free from the calyx, this 

 or its lobes deciduous. Ovules 2, penduhms, but seed almost always s(ditary. 

 Style terminal — Trees or shrubs, with bark exuding gum, and mostly as well as 

 the seeds yielding the flavor of pru.ssic acid. Stipules free, deciduous. 



1. Prunus. Flowers perfect. Carpel solitary. 



2. Nuttallia. Flowers polygamo-dieecious. Carpels and tliin-fleshed dru[)es 5. 



SuBOHUEU If. ROSA(JE/E i'koper. 



Carpels free from the persistent calyx (the limb of the latter rarely deciduous), 

 becoming akene.s, or in the hrst tribe hillicles, or oidy in Kuhus (where they are very 

 numerous) drupe-like in fruit, Stipules commonly adnate to the petiole. Calyx 

 dry and open, or sometimes strictly enclo.sing the fruit (one or two akenes), or in 

 Rosa fleshy and pome like enclosing numerous akenes. 



