594 
MR. F. 0. BOWER OX THE COMPARATIVE MORPHOLOGY OF THE 
general appearance, but not in position. They were not to be found upon the young 
leaves of the plant investigated, and this would point to a late origin, which, together 
with the irregularity of their arrangement, would give them the rank of emergencies. 
This cannot, however, be accepted as conclusive, since they are entirely absent from 
some leaves, even when mature, and that may have been the case with the young 
leases which were observed. However this may be, they are certainly not constant 
in occurrence nor in arrangement. 
In very young leaves, before the pinnse make their appearance, there are to be seen 
two lateral, basal wings, as represented by Warming (l.c,, Taf. 4, figs. 16-19) for 
Ceratozamia longifolia. As in other cases these may be traced upwards in the young 
leaf, and be seen to be continuous with the two lateral ridges, which run to the apex 
of the phyllopodium. The phyllopodium is thus, as in other cases, fundamentally a 
winged structure. As the leaf grows older the basal wings become elongated upwards as 
broad flaps (cf. Warming’s figure, l.c., Taf. 4, 19). Up to the time of appearance of 
the first pinnae there is no connexion between the flaps transversely across the face of 
the phyllopodium. At a later period, after the pinnae have begun to be formed, a 
more or less irregular and lobed extension of the wings is formed on the face of the 
phyllopodium, which connects the two wings one with another, and remains per¬ 
manently, so that it can readily be recognised at the base of the mature foliage-leaf, 
and may be found also on the ventral face of the scale-leaf. This connexion between 
the wings transversely across the face of the phyllopodium is interesting when com¬ 
pared with other examples of a similar process above described : thus in Todeci and 
in Angiopteris similar developments have been noted ; but there is a difference in the 
time of development : thus in Todea and in Ceratozamia the connexion appears at a 
comparatively late period, whereas in Angiopteris the transverse connexion is present 
from the first. 
As described by Warming, the order of formation of the pinnae is basipetal. This 
may be proved in the same way as in Encephalartos Barteri (Plate 40, fig. 40). The 
young pinnae are much like those of Zamia, but the margin is not undulated, but 
smooth. 
Zamia muricata. 
As statements have already been made by Karsten * as to the development of the 
leaf in this plant, it was important to observe the early stages of the process carefully, 
and especially so because his observations do not coincide with my own and with 
Warming’s on Macrozamia and Ceratozamia, &c. From the passages quoted it appears 
* Org. Betr. d. Zamia muricata, p. 197. He says: “Alle Fiederbliittchen erscheinen bei ilirem ersten 
Auftreten in der Form ba.lbmondformiger Wulste ; ” and later on, p. 211 : “Von mehr Bedeutung wurde 
fur den Vergleich der Cycadeen mit den Farren die Entwickelungsgeschicbte und Entfaltungsweise der 
Blatter gewesen sein, die bei diesen Familien gleichmassig von unten nacb oben fortsclireitet, Vi bread 
bei den iibrigen Phanerogamen die Entfaltung des Blattes von oben nacb unten.” 
