A SUMMER RAMBLE AMONG THE HEBRIDES. 151 



Associated with the numerous Pinnae of Pabba, we found a 

 delicately-formed Modiola, a small Ostrya, Plagiostoma, Tere- 

 bratula, several species of Pectens, a triangular univalve re- 

 sembling a Trochus, innumerable groupes of Serpulse, and the 

 star-like joints of Pentacrinites. The Gryphse are also abun- 

 dant, 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 con- 

 sequence 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 suc- 

 ceeded 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 explora- 

 tions, and return to the Betsey. The little wind had become 

 less, and all the canvass 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 



