Rhododendron arboreum

Turner, Ian M., 2015, The botanical legacy of Thomas Hardwicke’s journey to Srinagar in 1796, European Journal of Taxonomy 108, pp. 1-25 : 11-13

Rhododendron arboreum

Probably the most important of these Smith names is Rhododendron arboreum . Smith acknowledged that the species was based entirely on Hardwicke’s description and drawing. Hardwicke had included it as ‘Doubtful’ on pp. 359–360 in his paper but did not provide a name. Britten (1906: 240) wrote, in reference to drawing no. 40 in the Natural History Museum collection, ‘the drawing is practically the type of Exotic Botany, tab. 6’. I take this to be an effective lectotypification of Rhododendron arboreum Sm. to drawing 40. The use of ‘practically’ has a degree of ambiguity but in the literal sense – for practical purposes – it seems acceptable and it is clear that the section refers to Rhododendron arboreum . In the absence of any Hardwicke specimens, the choice of type seems limited to the illustrations which comprise drawing 40, a drawing in the British Library set (Vol. VII no. 23) and Smith’s published illustration (t. 6). Britten’s selection does not therefore present any problems, and, surprisingly, I have not found any other attempts to designate a type for this species.

Hardwicke’s description was used to validate another name. Raper (1810) produced a long report on another expedition to the same area of India as Hardwicke’s. This was communicated to the Asiatic Society by, the then President, H.T. Colebrooke. The published account in Asiatick Researches contains a number of footnotes – the first of which states that the note is by the President. Raper’s account mentions a number of plant species, mostly using vernacular names. For boorans, the native name reported by Hardwicke for Rhododendron arboreum , there is a footnote that gives the name Rhododendron puniceum Roxb. and a direct reference to Hardwicke’s description. This link provided by Colebrooke between Roxburgh’s name and Hardwicke’s description validates Rhododendron puniceum more than 20 years prior to its publication in Flora Indica. I lectotypify R. puniceum to the Plants of India copy of the drawing. In fact, Roxburgh did see the Hardwicke drawing of boorans. William Hunter, in a letter of 24 September 1797, included a request from Roxburgh for another copy of the drawing as his had been ‘carried away’ by Sir J. Murray (possibly Sir John Murray 1745–1822, Auditor General of Bengal).