JULY 26, 1918] 
petioles are appealed to as evidence of the 
existence of Medullosa in North America. Of 
course fronds are not evidence so it may be 
reassuring to state that characteristic sections 
of petrified stem material of Medullosa are 
contained in the collections of the U. S. Na- 
tional Museum, so that it may now be con- 
sidered proven that Medullosa foliage was, in 
life, borne on Medullosa stems in America as 
well as in Europe. It may be questioned 
(page 87) whether leaf form is more protean 
than either vascular anatomy or floral mor- 
phology. Apropos of Seward’s remarks on the 
genus Schiitzia it may be noted that in a paper 
which has apparently been overlooked, Schus- 
ter? describes specimens of Schiitzia anomala 
in the Dresden Museum, labelled in Geinitz’s 
handwriting, which show definitely that these 
objects were spore receptacles as had been sur- 
mised. 
The forms known as Microzania gibba (page 
504) and Zamites bohemicus (page 534) come 
from the Upper and not the Lower Cretace- 
ous. It would be far better if the term 
Wealden were used to denote a peculiar envir- 
onmental facies as shown in the lithology and 
not a chronological unit. There is no more 
reason for calling deposits in all parts of the 
world Wealden than there would be for calling 
the English Wealden deposits Potomac. 
On page 278 the genus Pelourdea is proposed 
for the long-known Yuccites vogesiacus of 
Schimper & Mougeot because the author con- 
siders it undesirable to retain a designation 
suggesting false ideas with regard to affinity. 
No one now supposes that this is suggested 
and such a proposal is entirely unwarranted 
and can only be confusing instead of clarify- 
ing. Moreover it is flying in the face of all 
eanons of nomenclature. A name of a genus 
is simply a name, and we use generic names 
for convenience chiefly, and not in a descrip- 
tive or phylogenetic sense. I imagine that 
fully 25 per cent. of the names in systematic 
botany and zoology are equally inappropriate 
3Schuster, J., ‘‘Uber die Fruktifikation von 
Schuetzia anomala,’’ Sitz. k. Akad. Wiss. Wien, 
Band 120, Heft 8, Ab. 1, pp. 1125-1134, Pls. 1, 2, 
1911. 
SCIENCE 
97 
for one reason or another but this does not 
afford any justification for attempting to re- 
place them. There is surely a difference be- 
tween retaining a degree of personal inde- 
pendence in the face of codes and the persist- 
ent refusal to recognize the fact that practises 
of this sort serve only to confuse the subject. 
Cordaianthus Pitcairne figured on page 266 
is merely a type of inflorescence and is scarcely 
entitled to a specific name. At B in the same 
figure (Fig. 480) there is figured from the 
Kidston collection, a specimen which is called 
Cordaianthus Volkmanni. ‘The latter belongs 
to the type of inflorescence which Grand’Eury 
called the gemmifer group, to which this spe- 
cimen does not belong, although it does belong 
to Grand’Eury’s baccifer group, and should 
probably be identified as Cordaianthus sub- 
volkmanni. The genus Holcospermum (page 
361) is hardly an improvement on Carpolithus, 
and it would seem that if form genera for 
seeds are worth anything at all then Holco- 
spermum should be referred to Zalessky’s 
genus Polygonocarpus. This last genus is 
mentioned under Polypterospermum on page 
323 where we are told that Radiospermum or 
Polypterospermum ornatum should probably be 
referred to it, while on page 358 we are told 
that this species affords another example of 
Polypterocarpus as this generic name is em- 
ployed by the author. Nowhere is the genus 
Polygonocarpus discussed (it is not even in 
the index) although it is of some importance, 
and, if one may judge-from Scott’s figures of 
Trigonocarpus Parkinsoni, is the proper name 
for his specimens of the latter. If the reader 
will turn to Seward’s Fig. 426 C he will see 
that the sclerotesta of Scott’s Trigonocarpus 
Parkinsoni is of exactly the type of Poly- 
gonocarpus. Now if this figure be compared 
with Fig. 425 on the opposite page, also called 
Trigonocarpus Parkinsoni, it must be appar- 
ent that the two do not represent the same 
seed or the many angles of the former would 
show through the partially preserved sarcotesta 
of the latter, which is not the ease, nor is it 
desirable on general principles to refer struc- 
tural material to form genera based upon 
easts. 
