Transactions of the Prussian Gardening Society. 95 



begun to be laid out in 1768, and in which the second example 

 of the introduction of American trees was afforded to Ger- 

 many ; the first having been given, a few years before, in the 

 Electorate of Hanover. 



To prevent the caterpillar (Phalse^na brumata minor i.) 

 from ascending trees, M. Hallmann fastens a broad strip of 

 paper round the stem; and on this lays a coating of linseed 

 oil which has been thickened over the fire. Every three days 

 this must be renewed. He had previously tried tar, but found 

 it dry much too soon. 



4. On the Coldivhich certain Trees and Shrubs txiill bear in Germany. 

 In this paper a judicious use has been made of an Essay 

 on the Geographical Distribution of Vegetables, published in 

 the Memoires du Museum d'Histoire Naturelle, t. xiv. 1827, 

 p. 356. A table is subjoined, showing the cold which dif- 

 ferent trees will bear at Carlsberg, Tiibingen, Hanover, 

 Munich, and Berlin. Many plants which thrive at the two 

 first places are killed at the last. The table embraces 709 

 species ; and might well bear transferring to our columns, but 

 it would fill half a Magazine; and, after all, it would be chiefly 

 of use to the closet botanist, to assist him in his generalis- 

 ations ; and such can generally have recourse to the original. 



5. On the Liverpool Potato, and a Black Wiiiter Radish. 



This Liverpool potato is said to be an early sort, without 

 blossoms, extensively cultivated in the fields in the neighbour- 

 hood of Liverpool, for the supply of the market. It is pro- 

 posed to try it in the sandy soils in the neighbourhood of 

 Berlin. The black winter radish is recommended for its 

 hardiness. 



6. On the Culture of the Blue Hydrangea. 



M. Fintelmann considers it clear that the blue colour of 

 the flowers of the Hydrangea is owing to the presence of iron 

 in the soil; sometimes the iron is found in peat earth, and 

 sometimes in loam or sand. To make sure of blue flowers, 

 he recommends the mixture with soil of a small quantity of 

 iron filings, or of rust of iron in any form ; say, about one 

 twentieth part. 



7. Descriptive Notices of Two North American Needle-leaved Trees. 

 By M. Schoch of Wdrlitz. 



These trees are the deciduous cypress, and the balm of 

 Gilead fir : the former grows to the height of 30 ft., and the 

 latter to 70 ft. in Germany. The resin called the balm of 

 Gilead is found in lumps beneath the bark of the tree in 



