40 EXPERIMENT STATION BULLETIN 354 



long lasting. Production records on this seedling variety indicate that it 

 will be profitable commercially and it is therefore being disseminated to 

 commercial propagators during 1944 and 1945 under the name of James 

 Macfarlane. 



Some promising hybrids have been obtained from a cross of Dianthus 

 plumarius with the greenhouse carnation. Dianthus caryophyllus. These 

 hybrids are all hardy and at least some of them are fertile. One selection 

 that tends toward perpetual flowering has been self pollenated and an F2 

 population is now being grown. Backcrosses between this selection and 

 other carnation varieties have just been made. From some of the genera- 

 tions now growing, or from later ones, it is hoped to get hardy carnations 

 that will flower in the garden from Alay to November. 



3. Saintpaulia 



To obtain more desirable sorts of this excellent houseplant, crosses 

 have been made between some of the better existing varieties. Two selec- 

 tions from a cross of Saintpaulia ionantha with Blue Boy are being in- 

 creased for testing purposes. These are dark-foliaged forms that seem to 

 have some resistance to ring spot, a common trouble of the African-violet. 

 These selections have been named Sapphire and Topaz and are now being 

 disseminated to commercial propagators for more extensive testing. 



Selections from a cross of Pink Beauty with Blue Boy have been back- 

 crossed to Pink Beauty and should give interesting plants with pink or 

 reddish-colored flowers. This work is slow; 12 to 15 months are required 

 to flower plants from seed and four to five months for seed to ripen after 

 a cross is made. All the known commercial varieties of Saintpaulia, six in 

 number, are being grown at this Station for comparison. 



4. Kalanchoe 



Many species of Kalanchoe are in use as houseplants throughout the 

 country. This genus of succulent plants and other similar ones from South 

 Africa and Madagascar are easy to grow but little improvement has been 

 done on them. An attempt to improve this group of plants was started in 

 1938 and some 10 or 12 interspecific hybrids have been obtained. These 

 hybrids are often self sterile and intersterile with other hybrids or species. 

 Occasionally, a seedling or two result from a mass of chaff, indicating that 

 even though the genetic make-up of the hybrid is jumbled, the chromo- 

 somes in the sex cells may, on rare occasions, arrange themselves properly 

 and fertilization results. These occasional seedlings are almost invariably 

 fertile and come true from seed, further substantiating the alcove 

 hypothesis. 



Seed of one of these fertile F2 plants from a cross of Kalanchoe Bloss- 

 fcldiana and K. flaiuniea is now being disseminated for testing by commer- 

 cial seedsmen. This variety has large flowers, garnet-red in color, with 

 leaves almost scarlet in color when the plants are grown under dry condi- 

 tions. The largest number of F2 populations heretofore obtained in this 

 breeding work will be flowered during the winter of 1944-45. 



5. Begonia 



Breeding work has been carried on for the past three years in order 

 to obtain more desirable forms of Begonia, another of the leading house- 

 plants. Double-flowered varieties of Begonia seniperflorens have been ob- 



