170 



ANNALS OF SCOTTISH NATURAL HISTORY 



APERA INTERMEDIA AS AN ALIEN IN 



BRITAIN. 



By A. BRUCE JACKSON. 



THIS interesting grass was first collected in England by my 

 friend Dr. W. A. Vice, who found it associated with other 

 aliens of Eastern origin on waste ground at Blaby Mill, 

 Leicestershire, in June 1903. A specimen was subsequently 

 sent to the herbarium of the Leicester Literary and Philo- 

 sophical Society, where I found it wrongly labelled Polypogon 

 monspeliensis, I submitted an example to Dr. Hackel, who 

 identified it with an undescribed species, Apcra intermedia, 

 Hackel, collected several years ago by Dr. Zederbauer on 

 the Erdchias-Dagh, a volcano in Asia Minor. A note embody- 

 ing this information appeared in " Journ. Bot.," 1904, p. 348. 



In 1906 Mr. James Eraser gathered, with other aliens, at 

 Leith docks near Edinburgh, a grass which I identified as 

 Apera intermedia from comparison with the Blaby specimen. 

 Its occurrence in Scotland was recorded by Mr. Eraser in his 

 paper on Scottish aliens ("Ann. Scot. Nat. Hist." 1907, p. 42). 



Last autumn I submitted a portion of a Leith specimen 

 to Prof. Hackel, who wrote as follows : 



The Apera contained in your letter is really A. intermedia, 

 Hack., though in one point it is less characteristic than the 

 specimen from Blaby you sent formerly. The sterile glumes 

 of true intermedia have somewhat elongated points (like 

 small bristles), those of the Leith specimen are pointed but 

 not bristle bearing. A, intermedia is somewhat intermediate 

 between A. Spica-venti and A. interrnpta, but nearer to the 

 latter. The chief differences are : 



Apera internipta, Beauv. 



Panicula interrupta ; rami primarii 

 plerumque breviores quam in- 

 ternodia, inter verticillos, raro 

 eos aequantes. 



Glumos steriles acutae, muticae. 



Gluma fertilis callo brevissime bar- 

 bulato, arista earn 5-6plo super- 

 ante terminata. 



Antheras .4-. 5 mm. longae. 



Apera intermedia, Hack. 



Panicula aequalis ; rami primarii 

 racheos internodia superantes. 



Glumas steriles (saltern superior) in 

 setulam brevissimam abeuntes. 



Gluma fertilis callo glabro, arista 

 earn 3-4plo superante ter- 

 minata. 



Anthero; 1.5 mm. longee (quam 

 gluma fertilis 2 mm. 

 parum breviores). 



longa 



