For reasons explained in Flora of New Zealand, Vol. 1, p. 947, the correct application of the name H. leiophylla is uncertain. Plants in cultivation under this name in Britain do, however, agree moderately well with Cheeseman’s description and also with the type material of V. parviflora var. phillyreaefolia Hook, f., which Cheeseman cited as a synonym of his V. leiophylla. Since the cultivated plants cannot be identified with any species recognised in Flora of New Zealand, it seems reasonable to retain the name H. leiophylla for them, at least until the difficult group to which they belong has been further studied.
These cultivated plants in many respects resemble H. gracillima, notably in bearing racemes that are disproportionately long in comparison with the leaves (5 to 6 in. long with peduncle, leaves about 11⁄4 in. long). But the corolla-tube greatly exceeds the calyx in length, whereas in H. gracillima it is only slightly longer.