Btj the Rev. Robert Walsh. 39 



ence near the base of the trunk. Though not mechanically 

 sensitive when touched, it is highly susceptible of the varia- 

 tions of the atmosphere. The pinnate foliage affords a thick 

 shade on a bright day, but when rain impends, or even when 

 a cloud passes over the face of the sun, the leaflets imme- 

 diately close their under surfaces together, and the tree 

 seems divested of its leaves. When the sun again appears, 

 the leaflets reassume their horizontal position, and expand 

 so speedily, that the motion is sometimes perceptible. The 

 flowers are still more beautiful than the foliage. They con- 

 sist of large pencils or clusters of stamens of a bright pink 

 hue, and rich silky texture, and hence the Turks, who are 

 particularly fond of the tree, have given it the soft and 

 fanciful name of Gul Ibrisim, the Silk Rose, and hence 

 is derived its specific name with Botanists. It is now found 

 in all the gardens of the Bosphorus, but it is not a native, nor 

 is it described by the ancients. 



Pistacia Terebinthus. 

 This tree was well known, and is accurately described by 

 Dioscorides,* Theophrastus,^' and Plin y.J Tiieopiiras- 

 tus, and Pliny after him, mention a singularity in the tree, not 

 noticed by modern writers, though very remarkable : Qepu $e 

 kx) xupuKeoSri Tivcc KoTXx, xa&a7T6£ 17 tttsXsx, Iv oTg Sypfiix eyytvsTctt 

 xwvo7roei$ri' lyytvercci tie ri gyTivuSeg sv tovtois xx) y\t<r%pov.§ In all 

 the trees of this species which I have met with, I have 

 observed this. A species of gnat, or aphis, forms a nidus at 



* Lib. i. cap. 91. t Lib. iii. cap. 14. + Hist. Nat. Lib. xiii. cap. 6. 



§ Lib. iii. cap. 14. It bears, like the Elm, follicles in which a gnat-like in- 

 sect breeds ; in these, too, is found a resinous, viscid substance- 



