1923) WILSON, THE HORTExXSIAS 239 



heads of sterile flowers should have remained unsuspected, at least so far 

 as books are concerned, for I have searched high and low and can find no 

 suggestion of it. Charles Maries in 1879 visited Oshima and there col- 

 lected bulbs of Lilium auratum var. platyphyllum Baker. He must have 

 seen this wild Hydrangea but I can find no record of its being men- 

 tioned by him although be did introduce two fine forms of Hydrangeas 

 which are named Mariesii and Veitchii. Different Japanese botanists have 

 visited Oshima and the other stations of the plant, but I cannot find that 

 any one of them has identified this or saw in it anything significant, 

 although Dr. T. Nakai informs me that he, for some time past, has been 

 aware of its identity, but has not published his conclusions. The wild 

 plant is a shrub from 1 to 3 m. tall with many stems forming a broad 

 bush which occurs either singly or many together making a dense thicket. 

 It grows right on the edge of the foreshore under the full influence of the 

 sea and also inland among volcanic detritus, but all parts of the localities 

 in which I know this plant to be wild are strongly influenced by the sea. 

 The plant is in fact simply and solely a littoral plant, an important point 

 to be remembered when you come to discuss Hydrangea serrata DC, with 

 which it is almost inextricably confused. The giving of a special varietal 

 name to the wild plant may conduce to clearness though there is nothing 

 to distinguish it from such garden forms as SiebokTs II. japonica (which 

 by the way is not the plant known in gardens today by this name) except 

 its entire petaloid sepals which may or may not be a constant character. 

 The Japanese name of this plant is Gaku or Gaku-bana. 



A form with blue flowers is: — 



Hydrangea macrophylla var. normalis f. coerulea Wilson, n. comb. 



Hydrangea Belzonii Siebold & Zuccarini, Fl. Jap. i. 109, t. 55 (1840). 

 Hydrangea Japonica var. caerulea Hooker in Bot. Mag. lxxii. t. 4253 (1846). 

 Hydrangea Hortensia /3. coerulea K. Koch, Hort. Dendr. 106 (1853). 

 Hydrangea japonica e. coerulescens Regel in Gartenfl. xv. 290 (1866). 

 Hydrangea Hortensia y. Belzonii Maximowicz in M6m. Acad. Sci. St. PStersb. 





6r. 7, x. no. xvi. 14 (Rev. Hydrang. As. Or.) (1867).— Hemsley in Garden, 



x. 266 (1876). 

 Hydrangea opuloides e. Belzonii Dippel, Handb. Laubholzk. in. 322 (1893). — 



Rehder in Bailey Stand. Cycl. Hort. in. 1621 (1915). 

 Hydrangea hortensis var. Belzonii Nakai in Tokyo Bot. Mag. xxxi (196) (1917). 

 Hydrangea opuloides var. japonica f. coerulea Rehder in Jour. Arn. Arb. in. 



43 (1922). 



This form is distinguished by its dee]) blue hermaphrodite flowers and 

 blue or white sterile ray-flowers. The leaves are ovate-elliptic to obovate. 

 As Rehder points out this is a very hardy form. 



Siebold figures for his 77. Belzonii a plant with obovate leaves in whorls 

 of three and states in the text that the leaves are ternate or rarely opposite. 

 I have seen no specimens with leaves so arranged though doubtless it does 

 occur on some cultivated plants. Siebold also states that the ray-flowers 

 are very numerous, being from 12 to 15, and he figures a fragment of an 

 inflorescence in which all the flowers are sterile. A co-type in the Gray 

 Herbarium of the plant referred by Maximowicz to his var. Belzonii has 





