50 NATURAL HISTORY OF PLANTS. 
Pithecolobium are very rare in Africa and Asia, though, on the contrary, 
widely spread in America. Mimosa, too, is chiefly American. As 
for Acacia, it is commoner in tropical and Southern Africa than many 
other parts of the Old World. The Floras of the Cape, Senegal, and 
Abyssinia include upwards of fifty species, but it chiefly affects a 
favoured zone in Australia and the neighbouring parts of Oceania, so 
that at the present day nearly three hundred species, that is, a 
little less than three-quarters of the entire genus, are known to 
occur spontaneously in New Holland. 
The Mimosee possess numerous properties,’ of which the most 
remarkable are the astringency of the bark and pericarp, and the 
presence of a gummy substance in the former, analogous to that of 
the Prunee. Gum arabic and all other gums resembling it in solu- 
bility in water, and chemical reactions generally, are furnished by the 
Mimosea, and also especially the genus Acacia.* It is well known that 
most of the gums called Arabic and Senegal gums are produced by 
A. arabica,’ a species spread over India, Egypt, Arabia, Senegal, and’ 
even as far south as the Cape. It has four chief forms or varieties,’ 
called xzlotica,’ tomentosa,’ indica,’ and Kraussiana.® It is the first of 
these varieties which, at least in great part, constitutes the J. vera’, 
of authors, a plant long supposed to be the only source of gum 
arabic. Senegal gum is exuded chiefly from the variety tomentosa, 
and the Indian gum from indica. However, in places whence such 
gums are obtained there are other Acacias of different species which 
supply it. Such are 4. adstringens,” giving gum gonaté or gonatié, A. 
1 Enpr., Enchirid., 6838.— Linph., Veg. ® Bentu., loc. cit. — H. Bn,, loc. cit., 94 A. 
Kingd., 552; Fl. Medic., 268.—Gu1B., Drog. 
Simpl., éd. 4, iii. 300.—RosEntTH., Syn. Plant. 
Diaphor., 1051, 1065. 
2-H. By., in Dict. Hneycl. des Sc. Medic., i. 
254; Révision des Acacia Médicinaux, in Adan- 
sonia, iv. 85. 
3 W., Spec., iv. 1085.—DC., Prodr., ii. 461, 
n. 135.—H. By., loc. cit., 91, n. 8. 
4 Bentn., in Hook. Jowrn., i. 500. 
5 4. nilotica Dev, Fl. Zigypt., 79.—A. 
egyptiaca Fasr.— Mimosa arabica Potr., 
Dict., Suppl., i. 19.—Spina egyptiaca Pxvx., 
Almag., 3.— Spina Acacie Lopry.—Sant, Sunt 
of the Egyptians (see GuIB., op. cit., iii. 363.— 
H. Bn., loc. cit., 95 B,). 
—Acacia arabica W., Spec., iv. 1085.—DC., 
Prodr., n. 134,—Neb-neb of Senegal.— Gommier 
rouge Neb-neb ADANS, 
7 Beytu., loc. cit.— Mimosa arabica Roxs., 
Pl. Coromand.,, ii. 26,t.149.— Acacia vera altera 
Prvux., Almag., 3 (Babool, Babula in Bengalli, 
Burbura in Sanscrit, Nella Tooma in Cingalese). 
8 Beytut., loc. cit.—H. Bw., loc. cit., 96 D. 
9 W., Spec., iv. 1085.—DC., Prodr., n. 184.— 
VaALM. DE Bom., Dict., i. 81. 
0H. By, loc. cit, 88.—A. Adansonii 
Guittom. & Prrr., Fl. Seneg. Tent., i. 249.— 
Mimosa adstringens Scuum. & THONN., Beskr., 
2.— Gommier rouge Gonaké or Gonatié 
ADANS. 
