204 THE LATE DR. NEWELL ARBER: CRITICAL STUDIES 
earlier figures (1820) assigned to L. diehotomum *. Thus Feistmantel’s 
(8. pl. 32. figs. 1, 3, 5) figures of L. diehotomum appear to me to relate more 
probably to a species of Lepidophloios. Lindley and Hutton’s L. Sternbergü 
(20. i. pl. 4) is a decortieated specimen and probably belongs to L. lyco- 
podioides. . 
Among the specimens figured by Geinitz (9. p. 34, pl. 3. figs. 1-12) under 
the name Sagenaria dichotoma there are probably included representatives of 
more than one species. Several of the specimens, at any rate, are clearly 
indeterminable specifically and others are very doubtful. AJl that one can 
conclude is that, if any of them represent Z. loricatum, it is probably figs. 8 
and 12, but I am not convinced that this is the case. Turning next to 
Zalessky’s synonymy, which includes several references common to Zeiller’s 
which have just been criticised, we find also a comparison with Roehl's 
(23. pl. 8. fig. 6 ; pl. 11. fig. 2) figures of L. dichotomum, both of which 
appear to me to be probably distinct from Z. loricatum as here defined. 
I should also be inclined to regard as distinct Ettingshausen's L. brevifolium 
(6. pl. 24. fig. 5 ; pl. 26. fig. 3) and also the Radnitz specimens attributed 
by the same author to L. Sternbergü (T. pl. 26. figs. 1, 2: pls. 27, 28). 
With regard to Sauveur’s figures I should reject as indeterminable 
L. minutum (24. pl. 61. fig. 3), while L. clathratum (24. pl. 61. fig. 4) may 
be L. ophiurus, though this is uncertain. 
Kidston's L. Glincanum (16. pl. 2. figs. 20, 21; pl. 4. figs. 37-40) appears 
to be L. ophiurus. 
Diagnosis of L. loricatum, sp. nova. 
Leaf bases approximate, separated by slight grooves, napiform and sub- 
imbricated or fusiform and non-imbricated, somewhat prominent, in napiform 
types as broad as high or slightly longer than broad, ou an average about 
5 mm. cach way or sometimes 4 mm. or less in breadth ; in fusiform ty pes 
twice:as long as broad or even more, up to 10 mm. long and up to 5 mm. 
broad, lateral angles reunded, lower angle nearly always prolonged, upper 
angle broadly rounded or blunt and short in napiform types, acute and pro- 
longed in fusiform types. Leaf scar situated at or below the upper limit of 
leaf base occupying the greater width or even the whole of the base, often 
set obliquely on the base, prominent, rhomboidal. Upper angle usually 
somewhat rounded, or all sides and angles nearly equal and acute. From 
the lateral angles two lines may diverge downwards and outwards, but soon 
merge in the margin of the leaf base ; these are often invisible. Prints of 
leaf scar three, the median being the most distinct. A punctate ligular scar 
occurs above the leaf scar. Sub-parichnoid scars always absent. Keel of 
* These were re-figured by Bischoff and Brongniart and in the editions of Buckland 
(5. i. p. 432 ii. p. 91, pl. 75). 
