Francis E. Lloyd — 30 — Carnivorous Plants 



is very irregular, but readily distinguished by the eye by the change 

 in color, due to absence of cuticle in zone 4. Under the microscope 

 there is a sudden transition from imbricated apiculate hairs to scat- 

 tered, very long, curved ones, characteristic of zone 4. Underlying 

 both zones there is a hypodermis of wavy, thick walled cells. The 

 lowest portion of zone 4 is quite smooth, is lined with a small, straight 

 walled epidermis, and is 6 cm. in depth. 



Sarracenia Jonesii. — Living material from Flat Rock, North 

 Carolina, collected by Dr. L. E. Anderson through the courtesy of 

 Professor F. A. Wolf, was examined and showed quite the same char- 

 acters of the epidermis and of zonation as have been described for S. 

 Drummondii and S. flava. Such differences as occur are those of the 

 shape of the hd, which is smaller and ovate, similar to that of S. 

 minor save that it is more erect and apiculate. The color is green, 

 veined with red, with no fenestrations. There are no glands in the 

 lower part of zone 3, or in zone 4. 



Morphology of the leaf. — Troll (1932) has summarized our knowl- 

 edge on this subject, adding his own views. 



Baillon (1870) compared the leaf of Sarracenia with that of 

 Nelumbo, expressing the opinion that "the wide but shallow cone 

 of the (peltate) leaf of Nelumbo becomes in Sarracenia deeper and 

 narrower in such a manner as to produce definitively the form of a 

 long, obconical trumpet," thus recognizing the relation between the 

 epiascidiate pitcher of Sarracenia with peltate leaves. 



As we have already seen, the pitcher consists of a spreading bi- 

 facial leaf base surmounted by a tubular, gradually widening pitcher 

 bearing a strong ventral wing and the foliaceous flap continued in 

 front as the nectar roll. When the ascidium fails of development, as 

 it sometimes does (as in S. flava, etc.), the leaf presents a certain 

 likeness to that of Iris and the phyllodia of Acacia sp. Asa Gray 

 (1895-7) designated the ventral wing or keel as a "phyllodial wing." 

 Various earlier authors (Lindley 1832, Saint-Hilaire 1840, Morren 

 1838, Duchartre 1867) regarded the pitcher as a leaf blade with the 

 margins fused, some of them thinking the tube to be the winged 

 petiolar region and the flap the leaf blade. Gray accepted this view, 

 saying, "they are evidently phyllodia." Of them, however, Morren 

 believed the flap to be only the apical portion of the leaf blade, the 

 most of which is involved in the tube. Macfarlane (1889-90) was 

 firmly of this opinion. He regarded the keel as compound of the 

 fused leaf edges, comparing the condition with that in the leaf of 

 Iris as he interpreted the anatomy of this. The single keel of Sar- 

 racenia is equivalent to the pair of apposed wings of Heliamphora 

 and the more widely separated ones in Nepenthes, according to the 

 nature of the fusion. The flap of Sarracenia is to be regarded as 

 compound of two pinnae, as is the lid of Nepenthes (1893). Troll 

 regards this view as false, based on a misconception of the mor- 

 phology of the Iris leaf, which he insists is congenitally a strictly uni- 

 facial leaf. He accepts Goebel's intrepretation that the Sarracenia 

 pitcher is a unifacial leaf in the form of a tube and turns to the de- 

 velopment of it for support. He recalls that in plants with sword- 

 shaped leaves the leaf blade (Oberblatt) arises as an outgrowth of the 



