228 BIRD FRIENDS 



known houses of the first group are those devised by 

 Baron von Berlepsch in Germany. He has made a 

 special study of woodpeckers' nests, collecting hun- 

 dreds of them, and he finds that they all agree in the 

 following features: the opening is always circular 

 and of unvarying size for each species; the lower 

 portion of the nesting-cavity is enlarged in a gourd 

 shape, and ends in a pointed trough at the bottom; 

 the inner walls are roughened somewhat to allow the 

 birds to cling to them more easily; and in the extreme 

 point of the nest are a few fine shavings. Baron von 

 Berlepsch has constructed a nesting-house embody- 

 ing all these features. The results following the use 

 of this house are very remarkable. Of five thousand 

 boxes hung up by Baron von Berlepsch in his own 

 woods, and of about ten thousand hung up in other 

 localities by state authorities, ninety per cent or over 

 were occupied. And this was true in some localities 

 where unsuccessful experiments have been tried in 

 previous years with other kinds of nesting-boxes. 

 These houses are being made and sold in large quan- 

 tities by a German manufacturer, and in one case 

 are being made and used on a large scale by German 

 state authorities. They are now being made by at 

 least two firms in this country. This type may be 

 made by splitting a limb in two and hollowing out 

 the inside of each half in the proper shape and then 

 fastening the two parts together by means of screws 

 or nails. 



