96 
the Committee, although they have found it necessary in the 
course of their report to refer to this important aspect of the 
question. 
ALGERNON FE. ASPINALL, 
Hon. Secretary. 
25th November, 1919. 
XII.—THELLUNGIA, A NEW GENUS OF 
GRAMINEAE. ; 
O. Srapr. 
About a year ago Dr. Thellung, of Ziirich, submitted to Kew a 
grass which had sprung up among the wool refuse of the worsted 
mill, Derendingen, near Solothurn (Switzerland). It was first 
observed in 1907, in some young specimens which flowered only 
imperfectly. One of these was submitted to Professor Hackel, 
who very hesitatingly suggested that it might be a species of 
Ectrosta. As such (“‘ Ectrosia? mutica, Hackel ad int.’’) it was 
without a description being en. An attempt made then 
by Drs. Thellung and Probst to grow it in a pot failed, and it 
was not until 1918 that good flowering specimens presented them- 
selves in the same locality where the plant had been found 
originally. The preceding summer (1917) having been very hot 
it is not improbable that the grass was thereby stimulated to 
more active growth and ample flowering. 
The rich alien flora around the Derendingen mill includes 
numerous grasses of Australian origin. An analysis of the grass 
soon showed that it could not be an Ectrosia, nor did a prolonged 
search among the Australian grasses lead to its identification. 
Argentina and South Africa were suggested as likely native 
countries, but with no better result. Fortunately the condition 
of the specimen was good enough to allow of a very complete 
examination of the floral structure, which was found to be very 
like that of a Sporobolus, but distinguished by the presence of 
several (mostly three and sometimes four) florets in each spikelet. 
Moreover the disposition of the spikelets in the inflorescence 
proved to be different. The very close relationship of Sporobolus 
and Hragrostis demanded comparison with the latter, and some 
of its closer allies as Leptochioa and Diplachne; but the strictly 
l-nerved delicate valves coupled with the fr 
grain excluded those genera and led again back to Sporobolus. 
Now Sporobolus, as we understand it at present, is a well defined 
* 
