factured. An old French naturalist, the Abbe Le
Pluche, tells us that "the Pinna with its fleshy tongue" (foot),--a rude
inefficient looking implement for work so nice,--"spins such threads as
are more valuable than silk itself, and with which the most beautiful
stuffs that ever were seen have been made by Sicilian weavers." Gloves
made of the byssus of recent Pinnae may be seen in the British Museum.
Associated with the numerous Pinnae of Pabba we found a delicately-formed
Modiola, a small Ostrya, Plagiostoma, Terebratula, several species of
Pectens, a triangular univalve resembling a Trochus, innumerable groups
of Serpulae, and the star-like joints of Pentacrinites. The Gryphae are
also abundant, occurring in extensive beds; and Belemnites of various
species lie as thickly scattered over the rock as if they had been the
spindles of a whole kingdom thrown aside in consequence of some such
edict framed to put them down as that passed by the father of the
Sleeping Beauty. We find, among the detached masses of the beach,
specimens of Nautilus, which, though rarely perfect, are sufficiently so
to show the peculiarities of the shell; and numerous Ammonites project
in relief from almost every weathered plane of the strata. These last
shells, in the tract of shore which we examined, are chiefly of one
species,--the _Ammonites spinatus_,--one of which, considerably broken,
the reader may find figured in Sowerby's "Mineral Conchology," from a
specimen brought from Pabba sixteen years ago by Sir R. Murchison. It is
difficult to procure specimens tolerably complete. We find bits of outer
rings existing as limestone, with every rib sharply preserved, but the
rest of the fossil lost in the shale. I succeeded in finding but two
specimens that show the inner whorls. They are thickly ribbed; and the
chief peculiarity which they exhibit, not so directly indicated by Mr.
Sowerby's figure, is, that while the ribs of the outer whorl are broad
and deep, as in the _Ammonites obtusus_, they suddenly change their
character, and become numerous and narrow in the inner whorls, as in the
_Ammonites communis_.

The tide began to flow, and we had to quit our explorations, and return
to the Betsey. The little wind had become less, and all the canvas we
could hang out enabled us to draw but a sluggish furrow. The stern of
the Betsey "wrought no buttons" on this occasion; but she had a good
tide under her keel; and ere the dinner-hour we had passed th