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EXPLANATION OF PLATES 29.
Fig. 7. Upper surface of Fossil Loligo from the Lias of Lyme Regis. A, A, Barbs of the Pen. B, B, Marginal bands. C, Axis of the Pen. d, upper plate of marginal band, having an unusually corrugated surface, which may be the result of imperfect growth of the transverse fibres; if fully expanded they would probably have resembled those of the subjacent Plate at d″. (Original.)
d'. Magnified representation of the rugous surface of d.
d‴. Magnified representation of the second plate of the marginal band, Fig. 7. d″.
e. Upper surface of second Plate of the shaft of the pen; here the transverse wavy lines predominate over the vertical straight lines; but both are visible.
f. Upper surface of third plate; here the vertical straight fibres prevail over the transverse wavy fibres.
Plate 29. V. I. pp. 232 and 234.
Fig, 1. Fossil Loligo from Lias at Lyme, in the collection of Miss Philpot, exhibiting nearly the same structure at figs. 6. 7. at Pl. 28. and containing beneath the pen, a very large Ink bag, D. The greater proportionate size of this Ink bag indicates a difference in species from fig. 3. (Mrs. Buckland. Original.)
Fig. 2. Loligo Aalensis from Lyme Regis showing the under surface or concave side, and the duct of the Ink bag distended with Ink. A.A. Barbs or filaments of the Pen; B.B. Marginal bands; C. Axis of Shaft; D. Duct of Ink bag. (Mrs. Buckland. Original.)
The wavy lines here seen between the Ink bag and the apex of the Pen, are the inferior terminations of the successive lamina? of growth; each
