or MAHOIN8 OP LEAVES, ETC. 23 



Diss.,' tab., 106) will show liow easy the passage is 

 from a peltate to a tubular leaf. In these cases the 

 tubular form may rather be due to df^atation thau to 

 cohesion. M. Kickx^ mentions an instance of the kind 

 m the leaves of a species of Nicofiana, and also figures 

 the leaf of a rose in which two opposite leaflets 

 presented themselves in the form of stalked cups. 

 Schlechtendal '^ notices something of the same kind in 

 the leaf of Amorpha frufi''<><" : Trevinnm-; ' in tluif ^f 

 Arlstolochia Sq}ho. 



M. Fuel* describes aleat' of I'oli/gotuitaiu inaUijlornin, 

 the margins of which were so completely united to- 

 gether, as only to leave a circular aperture at the top, 

 through which passed the ends of the leaves. The 

 Rev. Mr. Hincks, at the meeting of the British As- 

 sociation at Newcastle (1838), showed a leaf of a Tulip, 

 whose margins were so united that the wliole leaf 

 served as a hood, and was carried upwards by the 

 growing flower like the calyptra of a Moss. 



The margins of the stipules are also occasionally 

 united, so as to form a little horn-shaped tube. I jiave 

 met with instances of this kind in the common white 

 clover, TrifoUum repeiis, where on each side of tlu? base 

 of the petiole the stipules had the form just indicated. 

 That the bracts also may assume this condition, may be 

 inferred from the peculiar horn-like structures of Mar- 

 graacia, which appear to originate from .the union of 

 the margins of the reflected leaf. 



Tubular petals occur normally in some flowers, as 

 IIeUiboius\ Epi'medimnf Viola, &c., and as an excep- 

 tional occuiTence I have seen them in Banunculm repens, 

 while in Eranthk hye malls transitions may frequently 

 be seen between the flat outer segments of the perianth 

 and the tubular petals. To Dr. Sankey, of Sandywell 

 Park, I am indebted for the flower of a Pelargonium, 



' Bull. Acad. Roy. Bmxcllea,' t. xviii, p. i and p. 591. 



' ' LinnsBa,' torn. 13, p. 383, 



^ ' Vorhandl. Nat. Hist. Vemns,' 1859, Bonn. torn, xvi, tab. 3. 



' Pull. S<)c. Bot. Fr.; vol. i, p. G2. 



