. The Quarterly journal of the Geological Society of London. 3) may bean indication of theirform. Xo sporangia havebeen recognized. The imperfect and bro-ken specimen representedof the natural size intext-fig. 3 B, affords thebest example of the habit of the fertile frond; at the apices ofa few of the branchlets are portions of the spore-masses. Apiece of the upper part of the specimen is shown twice the naturalsize in fig. 3 B. The occurrence of the fertile segments or spore-masses in connexion with the slender branches is shown moreclearly in PI. XII, fig. 12 a, and in text-fig. 3 A. One of
. The Quarterly journal of the Geological Society of London. 3) may bean indication of theirform. Xo sporangia havebeen recognized. The imperfect and bro-ken specimen representedof the natural size intext-fig. 3 B, affords thebest example of the habit of the fertile frond; at the apices ofa few of the branchlets are portions of the spore-masses. Apiece of the upper part of the specimen is shown twice the naturalsize in fig. 3 B. The occurrence of the fertile segments or spore-masses in connexion with the slender branches is shown moreclearly in PI. XII, fig. 12 a, and in text-fig. 3 A. One of thespore-masses with its carbonized covering is enlarged in fig. 12 b;and in text-fig. 4 (p. 93) an attempt is made to show the formsassumed by these bodies, many of which are scattered through theshale. They are often strongly convex (text-fig. 3 C), and in a fewexamples, as, for instance, the upper of the two shown in fig. 3 C,there appears to be a continuation of the short stalk as a medianline or rib over the convex back of the spore-enclosing body. In. [A &B are of the natural by 2 diameters, and C by 9.] gnified Compare the segments of Sphenopteris fontainei Seward (94) pi. \i Vol. 69.] OCR KNOWLEDGE OF WEALDEN FLORAS. some specimens (for instance, A & E, text-fig. 4) the carbonizedcovering is broken at the distal end: there is, however, no decisiveevidence as to the nature of this structure, whether it is a capsuleor an inrolled fertile piece of lamina. The spore-masses, on sepa-ration from the covering and on treatment with macerating solution,show no indication of grouping into sporangial masses within thewhole group. Two of the spores are reproduced in PI. XIV, fig. 5,and text-fig. 2 B (p. 91). Text-fig. 4 E, below, represents in outlinepart of a carbonized covering, in which no cell-outlines are visible,with some of the spores beyond its ragged edge. Text-fig. 4 D Fig. 4.—Pelletieria valdensis : Acovering ; D —piece of axis ; 9 diameters.) -C, E, 4 F=spore-masses
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Keywords: ., bookcentury1800, bookdecade1840, booksubjectgeology, bookyear1845
