5U explanation OF PLATE 29. 
Fig. 7. Upper surface of Fossil Loligo from the Lias ol 
Lyme Regis. A, A, Barbs of the Pen. B,B, Mar- 
ginal 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. 
/. Upper surface of third plate ; here the vertical straight 
fibres prevail over the transverse wavy fibres. 
Plate 29. V. I. pp. 307 and 309. 
Fig. 1. Fossil Loligo from Lias at Lyme, in the collec- 
tion of Miss Philpot, exhibiting nearly the same 
structure as figs. 6. 7. at PI. 28. and containing be- 
neath the pen, a very large Ink bag, D. The greater 
proportionate size of this Ink bag indicates a dif- 
ference in species from fig. 3. (Mrs. Buckland. 
Original.) 
Fig. 2. Loligo Aalensis from Lyme Regis shewing the 
under surface or concave side, and the duct of the 
Ink bag distended with Ink. A. A. Barbs or fila- 
ments 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 termina' 
tions of the successive laminse of growth; each 
