AMERICAN OBNITIIOLOGY. 59 



shores of the Black Sea. Although somewhat shy, it is described as 

 having "sprightly manners and a clear, ringing trill." Odd indeed are 

 some of nature's evolutions, I had almost said caprices, for the rock 

 nuthatch is just as much at home and apparently just as happy on its 

 bleak precipices as is our merry white-breast in his umbrageous home 

 in the oak or maple forest. 



But what kind of nests do the rock nuthatches construct on their 

 limestone walls? That is one of the most interesting features of the 

 life of these birds. One writer who has observed them in their native 

 haunts describes the rock nuthatch as "an expert clay mixer and 

 moulder." The bird does not chisel out a nursery in the rock — no, in- 

 deed; his method of constructing his nest is as follows: Having found 

 a little hollow or indentation on the rocky wall, he will erect a cap or 

 dome of mortar over it, plastering the structure so firmly against the 

 surface that no rain or storm or predacious creeping thing can demol- 

 ish it until long after it has been abandoned by the little architect. 

 The circular base of the nest is ten or twelve inches in diameter. The 

 dome is not entirely closed up, but a small orifice is left in the center,, 

 upon the edges of which a narrow neck or funnel, also made of mortar, 

 is raised, the hole just large enough to admit the body of the bird. 

 The funnel is about three inches long. 



The building material employed is fine clay softened and glutinated 

 with the bird's saliva and mixed with plant fibers, for the little mason 

 does not believe in making bricks without straw. So well packed is 

 the inch-thick wall that a stiff knife blade must be used to cut through 

 it. While the natural color of the adobe cottage is ash gray, and 

 therefore harmonizes with the general hue of its surroundings, and also 

 with the mezzo-tints of the builder, yet he sometimes decorates it with 

 the gaily colored wings of moths caught in the chase and attached to 

 the plaster while it is fresh. The rock nuthatch is as expert a mixer of 

 mortar as the well known cliff swallows of our own country, and his 

 adobe dwellings bear a close resemblance to theirs. 



It is interesting to note that the European nuthatch, while nesting- 

 regularly in tree cavities, sometimes also chooses the crannies of rocks,, 

 when he goes a little more extensively into the plastering business; 

 but his skill is not so well developed as that of his oriental cousin, 

 whose mud cottage is a model of its kind. 



