xx Obituary. — David Thomas G ivy nil e- Vaughan. 
These four memoirs constitute a complete whole, but the observation 
of additional forms led to the publication, after an interval of four years, of 
a fifth memoir (K. and G.-V., 1914). 
The chief species described are Osmundites spetsbergensis (Nathorst) 
from the Upper Tertiary of Spitzbergen, and O . Carnieri , Schuster, a Para- 
guay species of doubtful age (Jurassic — Tertiary). 
The Spitzbergen species, though it shows no stem, is interesting from 
the fact that the structure of leaflets and sporangia is preserved, as well as 
that of the petioles ; it is a modern type, resembling Osmunda Claytoniana 
in petiolar structure, and O. regalis in the form of the frond. A solenostelic 
Fern stem was found burrowing among the roots of the Osmundites. 
O. Carnieri • is more remarkable. It is unusually large, the stem 
measuring 90 mm. and the stele 35 mm. in diameter. The vascular ring is 
in the form of several meristeles, each surrounded by its own endodermis, 
and including a varying number of bundles. The preservation is imperfect, 
but it is probable that the phloem extended all round each meristele, the 
structure thus being completely dictyostelic. This form is of great interest 
in conjunction with O. skidegatensis , and may lead to important conclusions 
when more is known about it. 
This completes the main series on Osmundaceae, but there are two 
small papers by Gwynne-Vaughan alone, dealing with recent members of 
the same group. The earlier of these, ‘ Some Remarks on the Anatomy 
of the Osmundaceae ’ (191 1), is concerned with the possible retention of 
the primitive features of fossil forms in the young plants of recent 
Osmundaceae. 
The chief definite character found to be retained is the mesarchy of 
the leaf-trace, occasionally occurring in early leaves of O. regalis. The 
ontogenetic evidence also favours the intrastelar origin of the pith and 
medullary rays. A full and acute discussion of the general question of 
Recapitulation is of remarkable interest. 
The final paper on the Order is ‘ On a Mixed Pith in an Anomalous 
Stem of Osmunda regalis ’ (1914). The abundant medullary tracheae met 
with in this specimen were evidently formed in response to an injury. The 
value of the observation depends on the credence attached to Jeffrey’s 
theory that traumatic characters tend to be ancestral. Accepting this, the 
evidence of the injured specimen tells in favour of the protostelic theory of 
Osmundaceous anatomy. The argument is a good one, as addressed to the 
Jeffrey school, but the morphological value of traumatic characters is still 
very much of an open question. 
The Osmundaceae work as a whole is perhaps unique as a study of the 
comparative anatomy of recent and fossil members of a definite group, 
ranging over so long a period of geological time. Certain points are still 
the subject of controversy, and some of the facts may admit of diverse 
