Washing Walls to destroy Insects. 535 



only to a certain size, and foi'ms mostly side-ovula, which, till 

 they are ripe, remain concealed by their coverings. It sometimes 

 happens, that, by a general deterioration of the organs of fructi- 

 fication, the fruit-axis grows into a branch, of which we have an 

 example in the double rose. The ovula are formed either fi'oni 

 the upper point of the undivided axis, as in Taxusand t/rtica (the 

 rudiment of the ovulum being, like the top of the bud, the first 

 and most important formation, and fixed on the chalaza, a part 

 similar to the medullary point and the surrounding medullary 

 enclosure), or they proceed from the metamorphosis of the pri- 

 mitive bud. In the latter instance they grow sideways out of the 

 axis, either at the base of the fruit-leaves, as in /Ranunculus, or 

 on the lengthened bundle of vessels of the medullary coat, which 

 is most usually the case. 



(To be continued.) 



Art. II. On the Utility of imshijig Garden Walls to destroy Insects. 



By W. P. 



I HAVE the management of some trees covering about 600 

 square yards of wall, which for geveral years had been so in- 

 fested with insects, that they neither bore fruit, nor made slioots 

 more than 1 or 2 inches long. I tried every means to get rid 

 of them throughout the summer, by washing them with various 

 mixtures, and also sfhoking them with tobacco, but it was of no 

 avail ; for, although it undoubtedly killed a great number of in- 

 sects, still the trees were soon again covered with them. As the 

 walls were old, and full of nail-holes, I conjectured that the 

 insects harboured there, and that if I washed the walls in the 

 winter when the trees were unnailed, with something destructive 

 to them, it would have a much better effect than any summer 

 dressing. The result proved that I was right in my supposition, 

 as the trees are now perfectly free from insects, have made ex- 

 cellent wood, and are loaded with fruit. 



The following was my method of proceeding. In the sprino- 

 I had the whole of the trees unnailed and tied to stakes driven 

 in the border ; I then washed the walls with the following mix- 

 ture : half a barrel of cement, one quarter of lime fresh from 

 the kiln, two bushels of soot, and 12 lb. of sulphur, mixed with 

 soap-suds to the consistency of whitewash. This was sufficient for 

 the quantity of wall mentioned; and it was done by a common 

 labourer. I may mention that part of the wall was covered with 

 moss, which now appears to be all killed. 



Hertfordshire, Sept. 4. 184'1. 



