G. M. Thomson. — On Donatia novaB-zealandise. 289 



Akt. XXXIV. — Note on Donatia nova3-zealandige, Hook,/. 



By GEORaE M. Thomson, F.L.S. 



[Read before the Otago Institute, 2dth June, 1880.] 



This interesting little plant, in the absence of the fruit, was placed originally 

 by Sii' J. D. Hooker in the order Saxifragese, and in his Handbook he 

 speaks of it* as the only representative in New Zealand of the herbaceous 

 tribe of Saxifi-ages proper. Up to within a very recent period, however, 

 its exact systematic position was matter of considerable uncertainty. A 

 few years ago, Baron Ferd. von Mueller expressed his decided opinion f 

 that its resemblances were so near those of Phyllachne, that it should be 

 placed along with that genus among the Stylidiere, and this opinion he 

 again published in Trimen's " Journal of Botany " for 1878, p. 174. In 

 the absence of fruit, however, this affinity could not be considered as finally 

 established. Mr. Petrie, Inspector of Schools for Otago, having recently 

 obtained, at considerable trouble, numerous specimens of Donatia in fruit, 

 forwarded them to Baron von Mueller, who has thus been enabled to prove his 

 former assertions. It is to be regretted that Baron von Mueller in publish- 

 ing the results of his last examination of the plant in question, should have 

 elected to do so in an Italian journal, instead of in one accessible to the ma- 

 jority of those interested in the subject. The following description of the 

 fruit and seed, together with the other information I record on the subject, 

 is translated from "Dal Nuovo Giornale Botanico Italiano," Vol. XI., N. 3, 

 (July, 1879) : 



" Fruit indehiscent, turbinate, completely bilocular, rarely trilocular, 

 flat on the top and almost tumid on its margin, about 2 lines long. Pla- 

 centse short, situated almost at the apex or above the middle of the dissepi- 

 ment. Seeds few in each loculus, rarely many ripening, pendulous or 

 patent, attached without a funiculus, obliquely ovate or ellipsoid, i-i line 

 long ; testa membraneous, dark, shining, reticularly striated ; hilum basal 

 with the chalaza at the extremity more strongly coloured, almost brown ; 

 raphe not prominent ; albumen amygdaline ; embryo very small, remote or 

 quite free from the hilum, often shorter than the albumen ; cotyledons ovate- 

 rotundate, almost equalling in length the central thin radicle, or the radicle 

 united with the cotyledons into an almost ovate body." 



Baron von Mueller regards the corolla of Donatia as gamopetalous, but 

 having its tube shortened or suppressed, as occurs in the Eubiaceous genus 

 Galium. The other points adduced are (1) the union of the stamens with 



* "Handbook of the N.Z. Flora," p. 58. f "Fragmenta," Vni., 39-41. 



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