Foreign Notices : — Holland. 4*65 



more time than I have at present, I should be most happy to communicate 

 what little knowledge I possess on this subject ; and also to send you speci- 

 mens of those insects which have been so injurious to our gardens round 

 Vienna this spring. The Curculio pyri, C. pomoriim, and P6nti« cratge^gi, 

 appeared in such numbers, and destroyed every bud so immediately after its 

 appearance, that, until the middle of May, the trees were without bud or leaf. 

 Even now these butterflies are so plentiful, that there is a bad prospect for 

 next year, although we searched for them in all their various metamorphoses, 

 and still catch thousands of them in the mornings and evenings, when they are 

 crowded together on diiferent flowering plants, especially on Valeriana rubra, 

 ZJelphinium Ajaci^, and Philadelphus sp. I intend making a collection of all 

 these injurious insects, and putting them into a frame and glass, for the in- 

 spection of those who may be desirous of knowing them. This will enable 

 young gardeners to know them at once, and at any time ; and, by reading their 

 different distinctive qualities, any one may easily remember their forms ; which 

 would not be the case, if a person were left to observe them in their different 

 states and seasons alone j therefore, 1 would recommend such a collection in 

 every garden. — C. Hauch. Rennweg, near Vienna, July, 1837. 



The very interesting and valuable work above referred to by M. Ranch 

 was published by the Agricultural Society of Vienna, who have also sent us 

 a copy of it. It is now being translated for us, and will very shortly be pub- 

 lished, in as cheap and convenient a form as possible, for the use of young 

 gardeners. M. Ranch's idea of forming collections of destructive insects, in 

 glazed cases, for the use of gardeners, is excellent, and we hope to see it 

 adopCed by many of our readers. — Cond. 



HOLLAND. 



Prizes offered by the Academy of Sciences at Haarlem, which held its eighty- 

 fifth annual meeting on the 20th of May last. The Academy's gold medal, and 

 a gratuity of 150 florins (12/. I65. 3d.), were awarded to Dr. C. F. Gaertner of 

 Calew in Wurtemberg, for a Memoir in German, on hybrid plants, obtained by 

 the fecundation of certain species with the pollen of others. 



The Academy pi^oposes the following Questions to be answered before January 

 1. 1839: — What are the different species of marine animals which destroy 

 piles, and other wooden structures, by perforating them ? According to certain 

 botanists, some algae, of simple structure, if placed in favourable circum- 

 stances, will develope themselves, and be changed into vegetables quite dif- 

 ferent, and belonging to genera much higher in the scale of organisation, 

 though these same algae, if not in favourable circumstances, would be fecun- 

 dated and reproduce their primitive forms. The Academy is desirous that these 

 observations should be extended to other vegetables, which have not yet been 

 examined under this point of view; and that the truth or falsity of this transi- 

 tion of one organised body into another be proved b}' exact descriptions and 

 detailed figures. It has often been observed that some plants, in certain cases, 

 give out a phosphorescent light, such as Tropae^oluui, Calendula, Lllium bulbi- 

 ferum, Taghtes, Euphorbia phosphorea, Rhizomorpha, &c. The Academy 

 wishes that, from researches made on purpose, this phenomenon may be ex- 

 plained ; that it may be determined how much of what has been said on this 

 subject is to be admitted as true; under what circumstances the phenomenon 

 takes place ; and what is the cause ? 



The following Questiojis were last Year 2})'oposed by the Academy, to be an- 

 swered before January 1, 1838 : — How is wood formed ? Does it take its origin 

 immediately from the sap, or from the cambium under the bark; or is it formed 

 by the vessels which descend from the buds and the leaves, as the observations 

 of M. Du Petit Tliouars, and of M. Giron de Buzareingues, seem to prove ? 

 What application can be made of a knowledge of the true manner in which 

 wood is formed, to the culture of useful trees ? The Academy desires, J st, 

 an explanation, illustrated by figures, of the metamorphoses of at least fifty 

 species of coleopterous insects, the metamorphoses and economy of which, 



Vol. XIII. — No. 91. ii h 



