252 R . £/. Compton. 
cylinder is usually somewhat coiled and twisted: it terminates 
below in the region of a leaf-node. No vascular connection was 
discovered between the bundles of the outer cylinder and those of 
the inner, either at the node at.which the latter takes its origin, or 
at any point of its course. The leaves and branches connect only 
with the outer ring of bundles. In a somewhat similar case 
described by Nestler 1 in Veronica longifolia, and also in the example 
of a tubular spadix of Peperomia maculosa described by de Vries, 2 
the internal surface of the funnel also gave off leaves and even 
flowers : but in the Mummy Pea no such structures have been 
observed. Further, in the case described by de Vries, the internal 
inversely oriented bundles are continuous with the medullary 
bundles normally found in the Piperacete, the connection being 
effected through a rotation of individual bundles. 3 In the Mummy 
Pea, however, the inner ring of bundles is quite independent of the 
outer, and is not connected by means of vascular tissues with the 
root system on the one hand, nor with the leaves and branches on 
the other. Under these circumstances it is perhaps surprising to 
find that the inner ring of bundles shews as complex an organisation 
as the outer “ normal ” ring (Fig. 2). All the usual tissues are 
present, the only difference being that the actual bulk of each 
tissue in each bundle is rather less than in a bundle of the outer 
ring. 
The central cavity of the funnel-like stem contains air and is 
bounded by an epidermis. The histological structure of this 
internal epidermis is very different from that of the external. 
Whereas the latter consists of narrow cells much elongated 
longitudinally and only seldom pierced by stomata, the internal 
epidermis is composed of much broader and less elongated cells, 
very thinly cuticularised and penetrated by a great number of 
stomata. The tissues abutting on the epidermis in each case are 
fairly similar : the inner cortex contains a considerable amount of 
chlorophyll, though not so much as the outer. 
It would thus appear that the whole internal complex of 
tissues, assimilatory, protective and conducting, functions in a 
1 A. Nestler “ Ueber Ringfasciationen ” Sitzungsb. d. k. Akad. 
d. Wiss. Wien (Math. Nat.), CIII., 1 Abth., p. 153, 1S94. 
2 H. de Vries. “ Sur un spadice tubuleux du Peperomia maculosa" 
Arch, neerl. des sci. ex. et nat. XXIV., p. 258, 1891. 
3 The case usually quoted as a ring-fasciation in Taraxacum 
officinale appears to be of a more complex type than those 
here mentioned: according to Reichardt (Verh. d. k. k. Zool. 
Bot. Gcs. in Wien., XIII, p. 1009, 1863) three rings of vascular 
bundles are present in the tubular scape. 
