-2H 



CAROTENOIDS 



Tetrahydrophytoene (eicosahydrolycopene ?) 



-4H 

 Phytoene (hexadeeahydrolycopene ?) 



4H 

 Phytofluene (dodecahydrolycopene ?) 



4H 



^-Carotene (octahydrolycopene ?) 

 4H 



^ Protetrahydrolycopenc 



I 



8- Carotene < Tetrahydrolycopene 



-4H 



-4H 

 Prolycopene^' Lycopene 



y- Carotene 



(0) 



Lycoxanthin 



(0) 



--^ Lycophyll 



[3- Carotene 



a-Carotene 



(Tangerine type). It was found that in each of these crosses the factors 

 for the red colour (lycopene) are constant ; Porter and Lincoln, 

 therefore, continue their reasoning as follows : " Pigments and colour- 

 less polyenes of the Tangerine type are not present or present only in 

 traces in the hybrids of the first cross. The lycopene content in the 

 hybrids of the second cross is not diminished from the content of this 

 compound in the red parent. Each of these crosses segregates in the 

 F2 into three red and one orange, or one yellow, respectively. The fact 

 that the factors for lycopene formation are dominant in both of these 

 crosses strongly suggests that the hydrogenation of lycopene to form 



