EXPLANATION OF THE PLATES. 339 



parallel that it is said to be pectinatcly-pinnatifid, or cleft like 

 the teeth of a comb (pecten). [ Othonna pectinata.] 



Fig. 6. — A pinnate or feathered loaf, not merely cleft, but presenting 

 parallel rows of leaflets, a. The adnate petiolar cleft stipule 

 (A Rose leaf). 



Fig. 7. — A bipinnate or twice pinnated leaf, said to be equally pin- 

 nate, as the pinnae end in even pairs. The base subtended by 

 thorny stipules. (Mimosa, species.) 



Fig. 8, 9, 10. — A series of leaves having their edges variously in- 

 grafted. 8. The sheathing linear channelled leaf of the Spi- 

 derwort ( Tradescantia virginica). a. The embracing margins 

 ingrafted together so as to produce a short, cylindric, uncleft 

 sheath ; in Grasses these sheaths are open to the base. 



Fig. 9. — Leaves of the Phormium tenax, or New Zealand Flax. 

 At b. they mutually sheath and are compressed. At a. a. the 

 sheathing margins unite or become ingrafted and are no long- 

 er sheathing, but above, the keeled leaf again expands, and pre- 

 sents the usual natural appearance of grass leaves. 



Fig. 10. — Is the leaf of a species of Iris; at a. it is open and 

 sheathing, bui at b. the two edges become ingrafted together, 

 so as to produce a very unusual leaf of a sword-shaped ob- 

 lique form, thick and rigid, and of the same appearance on 

 both surfaces. Fiom this form to that of the tubular leaves, 

 or ascidia of Sarracenia, the transition appears sufficiently 

 natural, as in 



Fig. 11, at a. The ingrafted edges of the leaf, like those of Iris, 

 are visible in the form of a dorsal leafy ridge, the base of the 

 petiole or foot-stalk is also open and sheathing, b. Represents 

 the midrib transformed into a ventricose open tube, surmount- 

 ed by an inclined auricular lid. The leaf of the Onion is alto- 

 gether tubular, yet other species of Allium present solid, flat, 

 or semicylindric foliage, not very dissimilar to the leaves of 

 Grasses ; such hollow leaves then, as those in question, have 

 the midrib hollow or inflated. In Lobelia Dort manna the 

 leaves have two longitudinal cavities, the unaltered midrib 

 forming a partition between the tubular cavities, which take 

 place in the laminae of the leaves. 



Fig. 12. — The curious ascidia of Nepenthes distillatoria attach- 

 ed towards the extremity of the leaf. a. The double dorsal 

 or foliar laminae, b. The tubular midrib. 



Fig. 13. — The curious ascidium of the Cephalotus follicularis of 

 New Holland, a circle of which around the scape or flower- 

 stalk are blended with a. the true leaves, b. The ventricose 

 pitcher with grooves and saliant ridges edged with bristly hairs. 

 c. The concave lid. d. The annulated margin, within pre- 

 senting a row of circular inflected hooks. 



