Colobanthus wallii Petrie
C. quitensis Hook. f. Handbk N.Z. Fl. 1864, 24 et auct., non Bartl. in Presl Rel. Haenk. 2, 1831, 13.
C. mollis W. R. B. Oliver in T.N.Z.I. 56, 1926, 5.
Type locality: Mt. Arthur, W. Nelson. Type: CM, "Mt. Arthur, Nelson, limestone rocks at c. 6000 ft. Jan. 1921, A. Wall." Endemic.
Plant forming cushion several cm. across and equally deep; branches up to 5 cm. long and branched, thickly beset with inflated persistent lf-bases. Lvs soft when dry, closely spaced but not us. imbricate; sheath short but obvious; blade linear, 5-10-(15) mm. long, without midrib or thickened margin, suddenly narrowing into very short apiculate tip. Peduncles short. Fls up to 5-(6) mm. long; sepals 4, broad, c. 5 × 2.5 mm., membr. but thickened at mid-base and at subacute or very shortly apiculate tip; stamens = sepals at flowering; capsule valves 4, < sepals. Seeds with low rounded papillae only.
DIST.: S. Mountains of Nelson; few records from east side of main divide in Canterbury and Otago.
FL. 11-12. FT. 12-4.
C. wallii was described from a single gathering. No type specimen is to be found in Petrie's herbarium at W, but at CM is the original material which Wall has labelled "C. wallii sp. nov. ined. Identified by D. Petrie". Correspondence between Wall, Petrie, and F. G. Gibbs, filed at A, makes it clear that Petrie had all this material when drawing up his description. The several specimens match Petrie's description well except that, though most fls are 4-merous, some have 5 sepals, sts associated with 5, sts with 4 capsule valves.
The stunted form of Wall's plants, which probably caused Petrie to regard them as novel, may well be due to high altitude or exposure, and is matched by a Cheeseman specimen at A (Raglan Range, Wairau, alt. 5000 ft., Jan. 1881, No. 4045). Otherwise neither Petrie's description nor the specimens themselves provide any reliable character to distinguish C. wallii from the larger and laxer plants attributed by Cheeseman (Man. N.Z. Fl. 1906, 66; 1925, 423) to C. quitensis, and recorded from Mt. Arthur among other places. Oliver (loc. cit.) pointed out that the N.Z. plant differed from Chilean examples of C. quitensis and gave to it the name C. mollis without either designating a type or discussing the relationship with C. wallii.