DETAILED DESCRIPTION OF ILLUSTRATIONS 167 



PLATE XVII, FIGURE 25. Upland orchard of lychee, revealing the tree, in 

 shape and size not unlike that of apple. The magnificent culture of these 

 trees of Huai chih variety as seen on these foothills establishes the fact that 

 it is not necessary to grow this tree along the streams if the rainfall is sufficient 

 during the fruiting season. Hsin T'ang, district of Tung Kuan, Kwangtung, 

 China, March, 1917. Photograph (No. 1150) by the author. 



PLATE XVIII, FIGURE 26. Lychee nurseries at the village of Fang Yung. 

 Lychee trees are very tender, especially when young and the nursery plantings 

 are protected from the cold winter winds by a magnificent hedge of mango 

 trees. Fang Yung, Tung Kuan district, Kwangtung, China, March, 1917. 

 Photograph (No. T 149) by the author. 



PLATE XVIII, FIGURE 27. Fang Yung nurseryman in his orchard of specially 

 selected and named trees, from which his nursery stock of lychee is propagated. 

 Fang Yung, Tung Kuan district, Kwangtung, China, March, 1917. Photo- 

 graph (No. 1148) by the author. 



PLATE XIX, FIGURE 28. A pair of Ta tsao Large crop lychee as seen in the 

 nursery village of Fang Yung, Tung Kuan district, Kwangtung, China, March, 

 1917. Photograph (No. 1147) by the author. 



PLATE XIX, FIGURE 29. Mr. Chan P'eng Cheung, nurseryman of Fang Yung, 

 seated under a beautiful specimen of lychee, the Hsi chio tsu Rhinoceros 

 horn variety. Notice the vines and lichens growing along the trunk of the 

 tree. Fang Yung, Tung Kuan district, Kwangtung, China, March, 1917. 

 Photograph (No. 1146) by the author. < 



PLATE XX. An acid peaty soil better for the lychee than an ordinary fertile 

 soil. On June 21, 1920, these two lychee plants were of similar size and 

 condition of health. On January u, 1921, when this photograph was taken, 

 the condition of the two was conspicuously different. The vigorous healthy 

 plant at the left had been growing for the seven months in an acid soil, con- 

 sisting of wo parts of upland peat to one of sand, while the weak unhealthy 

 plant at the right had been growing for the same period in an ordinary rich 

 soil made up of equal parts of loam, manure, and sand. (One-fifth natural 

 size.) Photograph from Frederick V. Coville. 



PLATE XXI. Healthy lychee root showing the mycorhizal tubercles. This is a 

 photograph (six times natural size) of a healthy root from a lychee plant grown 

 in an acid peat-and-sand soil. The tubercles are gorged with mycorhizal 

 fungi. Plants grown in an ordinary rich soil are small and weak and bear no 

 tubercles. Photograph from Frederick V. Coville. 



PLATE XXII. Enlarged sections of lychee root tubercles showing the cells 

 gorged with the mycorhizal fungus. Microphotographs by Dr. Emil G. 

 Arzberger. 



FIGURE a. Median longitudinal section of a tubercle, showing the fungus 

 mycelium in nearly all the cortical cells. (Magnification 195 diameters.) 



FIGURE b. Two of the outer cortical cells of a tubercle, showing the form 

 of the fungus mycelium. (Magnification 830 diameters.) 



