192 Transactions. 



Art. XXVI. — The Rediscovery of Ranunculus crithmifolius Hook f. 

 By Robert M. Laing, B.Sc. 



[Read before the Philosophical Institute of Canterbury, 7th December, 1910.] 



In the " Handbook of the New Zealand Flora " (1864), by Sir J. D. Hooker, 

 there is described as a new species Ranunculus crithmifolius. It was col- 

 lected by Mr. W. T. L. Travers at the Wairau Gorge, at an altitude of 

 6.000 ft. Hooker adds to his description the note that it is " a very singular 

 plant, easily recognized by its glaucous, fleshy habit, finely divided leaves, 

 and single-flowered short scapes." Mr. T. Kirk, in his " Students' Flora 

 of New Zealand" (1899), quotes Hooker's description, and adds — I know 

 not on what authority — the remark that only one specimen of the plant was 

 found by Travers. In Cheeseman's " Manual of the New Zealand Flora " 

 (1906), under the description appears the note, " A curious little plant, 

 which has not been collected since its original discovery nearly forty years 

 ago. There are no specimens in any of the New Zealand herbaria, and I 

 have consequently reproduced Hooker's description.'" 



In the " Plants of New Zealand," 1906, p. 170, alluding to this plant. 

 I wrote thus : "In spite, however, of all the perseverance and research 

 of modern workers, a few of the forms apparently known to the earliest 

 explorers have not been rediscovered in recent times. In some cases it is 

 probable that the plant has been redescribed mider a fresh name ; in a very 

 few cases it may be that by some lucky chance the first collectors fomid 

 a plant that on account of its extreme rarity has never been seen again. 

 In Ranunculus crithmifolitis we have a plant that has not been reidentified 

 since first found by Travers on the shingle-slips of the Wairau Gorge. Even 

 then only a single plant was seen. It seems more than likely, therefore, 

 that the plant was a casual variant of some other form than really a distinct 

 species. If, however, the original description is to be trusted, Ranunculus 

 crithmifolius is one of the most remarkable species of the genus. Like all 

 other shingle-slip plants, it is highly specialized ; otherwise it would not 

 have been able to live in the place whence it was reported. ... It has 

 leaves which, on a smaller scale, closely resemble those of the rock-samphire, 

 a plant of an altogether dift'erent order. They are thick, succulent, bluish- 

 green, and highly polished, thus differing widely from the normal leaf-form 

 of the genus. Diels compares them to the leaves of Ligusticum carnosulum, 

 which is one of the most singular species of the flora, and also [along with 

 Ranunculus Haastii] grows on the same shingle-slips in the Wairau Gorge." 



From these extracts it will be seen that Ranunculus crithmifolius was 

 what sailors call a " vigia " — something once reported but not again seen. 

 In January, 1910, I visited the Mount Arrowsmith district, and followed up 

 the course of a little stream flowing into the Cameron River on the westward 

 side of the Cameron Hut. The source of the stream was in a shingle- 

 covered ridge, some 5,000 ft. high. On the western side of this ridge I was 

 delighted to find a plant with all the characteristics of the shingle-slip 

 species, but one which was new to me. Specimens of it were scattered, a 

 few yards apart, over an area of several acres. It was by no means 

 <'ommon, and a close search was necessary to find it, as the leaves were of 

 the same colour as the shingle. Near at hand was growing Ligusticum 



