Notes on Asiatic Grasses: XXXIII

Abstract

Ischaemum barbatum Retz. was considered by Hackel in DC., Monogr. Phan. 6: 204 (1889) to be a subspecies of Ischaemum aristatum Linn. In this conception he was followed by J. D. Hooker (in Fl. Brit. Ind. 7: 127 (1896)) but there is no evidence that either of them ever examined the type of I. aristatum preserved in the Linnaean Herbarium in London, nor that of L barbatum preserved in the Retzius Herbarium at Lund. Indeed, had they done so, they could not possibly have come to the conclusion that the latter was in any way related to the former. Stapf did, however, examine the Linnaean specimens of I. aristatum, of which there are two sheets, 1214.2 and I214-3. The latter is the same species as Ischaemum ciliare Retz. and Stapf came to the conclusion that this sheet was true L aristatum of Linnaeus. A subsequent examination revealed that this conclusion was erroneous and that 1214.2 must be considered the type of I. aristatum as it more closely adheres to Linnaeus' description and moreover was collected by 'Osbeck in China'. True I. aristatum is very likely the species hitherto known as L crassipes Nakai. The Indian species (L ciliare Retz.) is properly known as I. indicum (Houtt.) Merr. based on Phleum indicum Houtt., Nat. Hist. II, 13: 198 (1782). Morphologically it is quite distinct from true L aristatum Linn.