128 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Lichi of China — a raisin-like fruit surrounded by a shell. 

 Ginkgo of China (fruit of maidenhair tree) — nearly always used cooked. 

 Water chestnut of Asia {Trapa bispinosa) — seed shaped like two horns. 

 Another water chestnut (Eleocharis tuberosa) — the corm or bulb is 

 eaten. 



Seed of Chinese olive (Canariwn) — oily but palatable. 

 Another species of Canarium (Java almond)— used to make emulsion 

 for infants' food. 



Candle-nut of Tropics — eaten after being thoroughly dried. 

 Paradise-nut of South America. 

 Cream-nut of South Africa. 

 True ' Butternut ' of the Tropics. 



Cashew nut of the Tropics — must be roasted or is poisonous. 

 Kingsland Chestnut. 



The Tabebuia from Zanzibar — seeds of a pumpkin-like fruit, oily and 

 fairly palatable — is grown at Porto Rico. — C. H. L. 



Oak Disease (Oidium quereinum). By P. Heriot and L. Daniel 

 (Le Jardin, vol. xxii. No. 517, p. 265 ; September 5, 1908).— In 1907-08 

 the oaks in France were attacked by a new pest, Oidium quereinum, 

 Thiensen, which covers the young shoots with a white powder, consisting 

 of ovoid spores (conidia) arranged in chains like those attributed to 

 other Oidia. Up to September 1908 (date of article), the nature of 

 the fungus had not been detected, but it seems probable that it is 

 Microsphaera alni which abounds on oak-leaves in the United States, 

 and has recently been reported from Geneva. Most species of Oak appear 

 to be attacked by it, e.g. Qucrcus sessiflora, pubescens, Toza, Ilex ; 

 it has not yet been detected on Q. Suber, and coccifera. It is suggested 

 that the disease may have originated in imported American oaks, but no 

 observations have been made as to whether these were the first attacked. 

 No adequate remedy is known, since it is impossible to cover a forest with 

 sulphur like a vineyard. 



M. Daniel in an interesting note points out that the trees beset by 

 the parasite are those which have been recently pollarded. In the 

 Departments of which he writes this takes place every seven years. Some 

 trees are completely pollarded, others are allowed to retain a central shoot, 

 while those destined for the carpenter are not trimmed at all, but are 

 allowed to develop freely. Now the fungus takes complete possession of 

 trees lopped in the previous autumn, when the mutilated tissues contain 

 a superabundance of water with no foliage to carry it off, while in 

 proportion as new growth has been made and there is a return to the 

 normal proportions of trunk and boughs, the parasite has so much the 

 less effect. The moral, according to M. Daniel, is obvious, and the 

 remedy lies in more judicious foresting. — F. A. W. 



OdontOgTOSSlim Leaf-spot. By M. C. Potter, M.A., F.L.S. {Gard. 

 Chron. 1909, i. p. 145). — A full account, with four figures of O. Uro- 

 Skinneri affected with this disease. — 67. W. 



Olearia. By S. Mottet {Le Jardin, vol. xxii. No. 517, p. 260; 

 September 5, 1908, 3 figs.). — The genus Olearia, known to us for the most 



