abstracts: botany, plant physiology 25 



BOTANY. — Kokia: A new genus of Hawaiian trees. Frederick L. 



Lewton. Smithsonian Miscellaneous Collections 60 : no. 5, with 



5 plates. October 22, 1912. 

 The new genus includes three species, Kokia drynarioides, K. lanceo- 

 lata, and K. rockii, the last two species being described as new. The 

 genus is based upon a study of herbarium material representing Gos- 

 sypiiim drijnarioides Seemann, from the Island of Molokai, Hillebrand's 

 variety of Seemann's species, from the Island of Oahu, and specimens of 

 a hitherto undescribed species collected in 1909 by Mr. J. F. Rock, of 

 Honolulu, on the slopes of the Volcano Hualalai, Island of Hawaii. 

 Kokia dry^iarioides and K. lanceolata are beHeved to have entirely dis- 

 appeared from the Hawaiian Islands, and the third species, K. rockii, 

 has been reduced to a single group of four trees. These are about 25 

 feet high, averaging 10 to 12 inches in diameter. F. L. L. 



PLANT PHYSIOLOGY. — A 'preliminary study of the forced curing of 

 lejnons as practiced in California. Arthur F. Sievers and Rod- 

 ney H. True, Bureau of Plant Industry. Bulletin 232. Feb., 

 1912. 



The process of forced curing of lemons in vogue in California con- 

 sists in subjecting the green fruit to heat and humidity in tight rooms 

 until the desired color is produced. The time required to accomplish 

 the result ranges from 5 to 14 days. 



Experiments are described showing that heat and humidity are of 

 secondary importance in the process and that the pungent, gaseous 

 combustion products from the oil-burning stoves used produce the 

 desired effect. It is suggested that these gases could be used on a com- 

 mercial scale by generating them in separate structures from which 

 they could be distributed to the different rooms containing the fruit. 

 Such conduction of the gases by means of pipes was found by experi- 

 ment not to impair their effectiveness. 



The loss of stems from the fruit has been a common result of the forced 

 curing process. It has generally been held that the high humidity which 

 obtains in the curing rooms was the cause of this trouble. The experi- 

 ments here reported prove that the' same factor which effects the color- 

 ing, also causes the loss of the stems. 



A study of the different materials used in the construction of curing 

 rooms relative to their effect on the coloring brought out the fact that 

 material of a porous nature hastens the process. This would indicate 



