800 THE JOUIIN^AL OF BOTANY 



have a higher average of rays than the younger flowers on the same 

 plant. 



Two further illustrations may he given of the correlation of the 

 average numher of stigma-rays with the amount of food available. 

 A set of 9 very starved plants gathered subsequently had an average 

 of only 4-1 rays, two of the flowers having only 3 rays each, the 

 lowest number hitherto recorded. The 3-rayed flowers had 6 stamens 

 each, and one of them had also a single theca on the margin of one 

 of the petals, deduction of the stamens in Papaver to 6 has been 

 observed by Goebel in starved plants (Einleit. Experim. Morphol. Pfl. 

 131; 1908). On the other hand, 107 capsules and flowers on a 

 group of plants cultivated in the Herbaceous Ground at Kew gave an 

 average of 7'2 stigma-raj^s, eight flowers having 9 rays each, and 

 only five having as few as 5 rays. The following table shows the 

 relative frequency of the various numbers of stigma-rays in the 

 328 flowers examined ; separate figures being given for the weeds 

 (221 flovsrers) and the cultivated plants (107 flowers) : — 



In the weeds the commonest number of stigma-rays was 5, and 

 the average 5*1 ; in the cultivated plants the commonest. number was 

 7, and the average 7*2. WoodrufFe- Peacock found that the stigma- 

 rays varied from 4 to 7, with an average of 6, in 100 flowers of 

 P. dubium taken at random ( Journ. Bot. 1913, 48). 



In 45 ca])suies examined by C. E. Salmon the number of rays 

 varied from 5 to 9, with an average of 7*4 (New Phyt. xviii. 114; 

 1919). Figures derived from capsules only will on the whole be 

 higher than those from flowers, inasmuch as a certain proportion of 

 the younger fiowei's will be excluded owing to their never maturing. 



The possibility of the existence in P. duhium of several races, 

 each with a different average of stigma-rays under the same con- 

 ditions, should not be overlooked. This is a matter for experimental 

 cultivation. 



SHORT NOTES. 



A CoREECTTON. [The following correction relating to Dr. Barn- 

 hart's paper on " Plant Nomenclature," published in our last issue, 

 reached us too late to prevent the publication of the passage. — 

 Ed. Jourx. Bot.] If it is not too late, 1 would suggest the omission 

 of everytliing under Mr. Sprague's fifth point [p. 257], except the first 

 sentence : that is, omit from the words " Hill's work of 175G " to the 

 end of the paragraph. My remarks about Hill's double generic names 

 ■were only incidental, having no bearing upon the point there discussed. 

 I have since discovered that they are provided for under the Vienna 



