Art. XIII.—An Undescribed Species of Cotula from the Chatham Islands.
[Read before the Philosophical Institute of Canterbury, 2nd December,1914.]
Cotula Renwickii sp. nov.
Herba perennis, erecta, circ. 1.2 m. alta. Caules stricti, sublignosi, viridi, cicatricibus foliorum annulati. Folia obovato-spathulata, ± 4 cm. longa et ± 14 mm. lata, glabra, membranacea, 5-nervosa, basi aliquanto dilatata, apice 3–6-crenata. Capitula 11 mm. diam., flavida; pedunculi 11 mm. longi, vix pilosi pilis brevissimis albis; involucri bracteae, 2-seriatae, circ. 12, oblongae, 4 mm. longae, glabrae, apicibus scariosis. Radii flores multiseriati; corolla ovoidea, basi dilatata obscure dentata; disci flores numerosi, 4-dentati.
Hab.—Chatham Islands: Growing on the clifis of the small islets known as the Forty Fours. Named after Mr. Renwick, of Ouwenga, Chatham Islands.
C. Renwickii is evidently closely related to C. Featherstonii, but easily recognized by its greater stature, its stems ringed with old leaf-scars, its thin glabrous leaves, those of C. Featherstonii being thickly covered with brownish hairs and somewhat succulent, its shorter peduncle and its much larger flower-heads, which, according to Mr. Renwick, are of considerably greater size than as given in the above description.
I only possess one small scrap of the plant,* so the diagnosis will probably need considerable modification and amplification. The specimen was kindly sent to me by my friend Mr. F. A. D. Cox, who had received it from Mr. Renwick, he in his turn having got it from certain fishermen. These latter while in the vicinity of the Forty Fours, managed one day to effect a landing—a by no means easy matter—and, while climbing the cliff, some of the plants were broken off. These, falling into the sea, were picked up by those in the boats and taken to Ouwenga, where they came into the possession of Mr. Renwick, who managed for a time to cultivate one plant.
The species is of more than common interest, since, on the one hand, it is so closely related to C. Featherstonii, a species hitherto supposed to be quite unlike any other member of the genus, and, on the other hand, it is possibly restricted to the small area where it was discovered, or, at most, it may eventually be found on one or other of the islets of the Chatham Group.
The station, as given above, tells little about the actual habitat. The growth-form is not in the least that of a true rock-plant. The closely related C. Featherstonii is supposed to grow only on peat, where mutton-birds nest, and perhaps this new species is restricted to some definite habitat. Mr. Cox is endeavouring to procure more specimens, so that before long something more should be known regarding this interesting species.
[Footnote] * Since writing the above description Mr. D. Petrie has most kindly lent me another specimen, a portion of the same gathering.