CETEROS 
NOTES ON CALAMOPITYS. 223 
Eristophyton fasciculare. In the other species of LHristophyton, however, 
E. Beinertianum, embedding is at least as rare as in the species left in 
Calamopitys. We may cite the small endarch strand shown in Phot. 26, 
evidently cut low down in its course, but still in contact with the secondary 
wood. This character varies in both groups, and affords no criterion between 
them. That it sometimes occurs in Calamopitys proper is a point of interest, 
but not one on which I should lay much stress. Its recurrence in Pitys may 
indicate that it is rather a primitive character. At any rate it does not 
constitute a difference between Calamopitys and Eristophyton. 
A second argument is based on the structure of the pith. In Calamopitys, 
as the author truly says, the groups of sclerenchymatous cells with dark 
contents, so conspicuous in Hristophyton Beinertianum, are completely absent. 
But they are likewise absent in the pith of ristophyton fasciculare ; 
the possible secretory sacs in the latter plant bear no resemblance to the 
sclerotic nests of Æ. Beinertianum ; the presence of these structures in the 
pith is a specific and not a generic character, and again affords no distinction 
between Dr. Zalessky’s two genera. 
In one other instance this author has attributed generic value to a character 
which proves to be, at most, only specific. He mentions that in C. Saturni 
some of the medullary rays are gradually enlarged outwards, while this is 
not the case in the Eristophyton species (l.c. p. 26). But, as we have seen, 
it is not the case in Calamopitys annularis either, and is therefore of no 
value as a distinctive character between Calamopitys and Eristophyton. 
The argument from supposed dimensions has been dealt with on a previous 
occasion (Scott, 1912, p. 1027). Dr. Zalessky estimates that in his Callizylon 
Trifilievi, a plant which he regards as allied to Eristophyton, the stem when 
complete may have attained a diameter of a metre. He thinks it improbable 
that the stems of Cycadofilices, with their fern-like foliage, should have 
reached such dimensions. The argument is at best a very indirect one, but 
Iam quite willing to grant that Eristophyton Beinertianum, at any rate, is 
likely to have had a thick stem. If this were so, the fact would not afford 
the slightest presumption against the plant belonging to the Cycadofilices. 
Besides the case of Medullosa stellata, in which a decorticated stem measured 
48 x 45 cm. in diameter (Weber & Sterzel, 1896, p. 25), we may cite that 
very primitive member of the Cycadofilices Protopitys Buchiana, a stem of 
which, though doubtless incomplete, was also almost a foot and a half thick 
(Solms-Laubach, 1893, p. 198). The question of dimensions is, in fact, quite 
irrelevant to the issue. 
We now come to Dr. Zalessky's more serious grounds for the separation of 
Eristophyton from Calamopitys. The chief of these relate to the structure of 
the secondary wood. Our author lays great stress on the difference in the 
medullary rays, high and multiseriate in Calamopitys, low and usually 
uniseriate in Eristophyton. The great difference, in typical cases, is strikingly 
