The Anatomy of Palm-Roots. 
19 
Once inside the moist stomatal chamber the Uredine is in 
similar case to other fungi which penetrate directly into an 
epidermal cell from the outside, for it has now to penetrate into the 
mesophyll cells (by its haustoria.) It is however much better off 
than such other fungi, being in no danger of dessication and having 
moreover little or no cutin to penetrate ; this may be one cause 
which has contributed to the present pre-eminence of the Uredineae 
among the parasitic fungi. 
W. L. Balls. 
THE ANATOMY OF PALM-ROOTS. 1 
ON SIDE RING the uniformity shown by roots in the general 
type of their vascular structure, all exceptional cases have a 
special interest. Von Mohl discovered deviations from typical 
structure in the roots of palms, and certain examples have been 
examined in detail by Cormack, and others. We now have in 
Dr. Drabble’s work a comprehensive treatise on the root-structure 
in this natural order. 
The paper deals with more than sixty species of Palms, and 
is divided into two parts. The second of these is devoted to 
separate descriptions of root structure for each species, while the 
first part contains a more general description arranged under dif¬ 
ferent headings and followed by the theoretical conclusions. 
All the component tissues of these roots were examined in 
detail, and thus a large number of valuable data have been accu¬ 
mulated. The chief interest of the subject naturally belongs to the 
different types of vascular structure present, but a few other 
matters should also be mentioned here. 
The author (p. 441) confirms “ Buscalioni’s account of the 
centrifugal appearance of the xylem-elements of the bundle in the 
roots of Monocotyledons, followed by centripetal lignification.” 
This is probably not a very restricted phenomenon, nor of any 
special importance. It may be seen in the roots of some ferns, 
and presumably in many other cases where the tracheides of the 
metaxylem are very large. 
An interesting fact observed in the case of the adventitous 
1 On the Anatomy of the Roots of Palms, by E. Drabble, D.Sc. 
Trans. Linn. Soc., II. Series, vol. VI., p. 427, 1904. 
