15 



, tries bordering upon the Atlantic Ocean. In no case has the mate- 

 rial thus sent proved to be correctly determined, being usually 

 mislabelled as P. Niruri L. or P. lathyroides H.B.K. These mis- 

 determinations are not always excusable because P. nummulariae- 

 folius not only manifestly differs from both those species and their 

 nearest allies, but represents in the American flora a type of vege- 

 tation that has no immediate relatives. Its affinities are African and 

 Asiatic. 



Leandri, who has contributed several specimens to our herba- 

 rium and has extensively collected this weed in its endemic range, 

 that is, Madagascar and the adjacent islands, is the author of a 

 critical study (in Lecomte Not. Syst. 7[4] :168-169, 171-172, 1939). 

 Here, he stresses the impossibility of using the relative size of the 

 leaf and the length of the fruiting pedicel to separate, even tri- 

 nomially, the many polymorphous aspects of the species. Leandri 

 treats P. tenellus Roxb. as a synonym of P. numinulariaefolius, a 

 disposition which is fully justified by the material of the latter 

 which I have seen in the Kew Herbarium, part of which at least 

 was seen by Hooker when preparing the classic illustration of 

 P. tenellus (in Hook. Icon. 16: PI. 1569. 1887). It is quite evident 

 that P. minor Fawcett (in Jour. Bot. 57:65. 1919) is a synonym 

 of P. nummulariaejol'ms, from which Fawcett attempts to sepa- 

 rate it on the basis of minor vegetative characters. An isotype of 

 P. minor in the herbarium of the N. Y. Botanical Garden, Harris 

 12123, fully matches specimens of P. nummulariaefolius such as 

 grow in moist and shady situations in a hothouse. I believe, more- 

 over, that Lanjouw is justified in suggesting (in Rec. Trav. Bot. 

 Neerl. 31:452. 1934) that P. corcovadensis Muell. Arg. is a 

 synonym of P. nummulariaefolius and an African weed introduced 

 into America. I have not yet seen authentic material of Mueller's 

 species, but its description and illustration (in Martins Fl. Bras. 

 11 [2] :30, PL 6 ii. 1873) apply to no other plant better than to 

 Poiret's Phyllanthus. 



Rio de Janeiro apparently was the original point of introduc- 

 tion of this noxious weed into America, having been brought there 

 probably by ships sailing in colonial times between Mauritius and 

 Brazil. I may note that this is not the only record of an introduc- 

 tion of the kind. Euphorbia spathulata Lam., the holotype of which 

 I have seen, is supposed to be endemic to the Plata regions of 



