icer.] XXVII. SAPINDACEiE. 109 



Of the genus Maple, upwards of 40 species are known, which are spread 

 over Europe, Asia, and North America. Not less than 11 of these are found in 

 the Himalayan region, 4 of which, A. sikkimense, Miquel, Thomsoni, Miq., 

 Hookeri, Miq., and Campbelli, H. f. & T., belong to the Eastern Himalaya. 

 Several of the N.W. Himalayan species have a wide range of distribution : A. 

 oblongum is found in China ; and A. pictum, Thunb., is known from India 

 under the name of cullratum, Wall., from the Caucasus, Armenia, and North 

 Persia, under the name of Icetum, C. A. Meyer, and it is closely allied to A. Lo- 

 belii, Ten., from the mountains of South Italy. As regards their geographical 

 distribution, the species of Maple may be divided into four large groups : first, 

 those of Europe and Western Asia, of which A. tataricum, L., pseitdoplatanus, 

 L., campestre, L., platanoides, L., opulifolium, L., monspessulanum, L., are 

 well-known species ; secondly, those of the Himalayan region ; thirdly, those of 

 Japan, China, and North-East Asia ; and fourthly, those of North America. Two 

 species, A. spicatum, Lam., and .4. pennsylvanicum, L. (rufinerve, Sieb. et Zucc), 

 are common to Japan and North America ; the others, of which the Japanese and 

 Chinese species, A. pahnatum, and the North American, A. saccharinum, Wan- 

 genheim, may serve as instances, are at present only known as endemic. The 

 following is a conspectus of the seven species, which are known from North- 

 West India, but the present classification of this genus is imperfect. A revision 

 will probably have the effect of basing it more upon the character of the inflor- 

 escence, the parts of the flowers, and possibly the structure of the seed. The 

 inflorescence of Acer is mixed, cymes arranged in racemes or panicles. 



I. Leaves undivided, rarely 3-lobed, penniveined, the lower 2 



or 4 lateral nerves often proceeding from the base. 

 Petioles half or one-third, the length of leaf ; flowers in 



hairy corymbs . . . . . . . .1.-4. oblongum. 



Petioles one- fourth the length of leaf, or less ; flowers in lax 



glabrous panicles . 2. A. Icevigatum. 



Allied to these two are of Himalayan species, A. sihhimense, Miq., Sikkim, Bhutan, 

 7000-9000 ft. ; Hookeri, Miq., Sikkim, Bhutan, and Assam ; Thomsoni, Miq., Sikkim : 

 and of the other species mentioned above, A . tataricum, L. , a small tree with white 

 flowers and red wings, which is at home in Eastern Europe, Russia, Western Asia, as 

 far as Northern Persia, and has been found in Mantchouria and Japan. 



II. Leaves 3-lobed, with 3, rarely 5 basal nerves ; flowers in 



terminal fascicles . . . . . . . 3. A. pentapomicum. 



Of the species mentioned, A. monspessulanum, L., a shrub or small tree, of Middle 

 and South Europe, Algeria, Syria, and Armenia, with small, coriaceous, 3-lobed 

 leaves on long petioles, belongs to this group. 



III. Leaves 5-lobed, with 5 basal nerves ; flowers in racemes 



or panicles. 

 Flowers in long lateral racemes, appearing before the 



leaves ; young leaves and inflorescence hairy . . 4. A. villosum. 

 Flowers appearing with or after the leaves in short racemes 

 or corymbs. 



Lobes of leaves short-acuminate, with obtuse ser- 



ratures ; leaves pale beneath . . . . 5. A . cazsium. 

 Lobes long- acuminate, with sharp serratures . 6. A. caudatum. 



Near these are, of Indian species, A. Campbcllii, H. f. & Th., from Sikkim ; of the 

 European Maples, the common Maple, A. campestre, L., with divaricate wings, small, 

 obtuse-lobed leaves and erect corymbs ; and the Sycamore, A. pseudoplatanus, with large 

 leaves, pale beneath, and hanging racemes, the first a moderate-sized, the second a 

 large tree, common in Europe and Western Asia. Two other species of this group 



