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5. The honey-streak: 



Without streak (erad = eradiata): occasionally in plants of 



hybridal origin. 

 With non furcate streak (n.furc). 

 With furcate streak (jure). 



6. The colours of the petals: 

 Yellowish white (albid): typical arvensis. 



And the colour-variations of tricolor: Blue (viol), Bright 

 yellow (lut), Rose-red (or red-lilac) (rosea), a Pale blue (pall — 

 pallida), Pure white (alba). 



The colours must be determined upon elder flowers. 

 Most of these variations were mentioned in the paper from 1921. 



7. The length of the spur: 



It is not expedient to state the length of the spur in absolute 

 measures, because it is dependent on external conditions. 

 In determining the length of the spur I have applied the 

 ratio between the length of the appendices of the sepals and 

 the length of the spur, because this ratio is very easy to 

 determine. Both the size of the appendices and the length of 

 the spur are varying dimensions, and they are in some way 

 independent of each other, so that the ratio to some extent is 

 the result of two varying characters. 



V. arvensis has a spur as long as the appendices or a little 

 shorter. V. tricolor's spur is a little longer. But in the dunes 

 of West-Jutland and Læsø, types of tricolor are found, whose 

 spur is more than twice as long as the appendices (fig. 1 c). This 

 ratio is due to both the long spur and the short appendices. 

 As I have used this character to determine the variation of 

 plants from dune populations, I have only distinguished the 

 following two types: 



Short spur (brev.calc = brevicalcarata) : the length of the 

 spur twice the length of the appendices or less. 



Long spur (long.calc = longicalcarata): the length of the 

 spur more than twice the length of the appendices (fig. 1 c). 



8. The form of the spur: 



Spur straight (rect.calc = calcar rectum): the most com- 

 mon type. 



Spur bent upwards (incurv.calc = calcar incurvatum): 

 most commonly found among the tricolor-types with long 

 spur from the dunes. 



