MOLLUSCA. 7;5 



Mya truncata, L. Op. cit. iii. p. 66, v. pi. 50. f. 2. 

 Abundant off the mouth of the Eden, and on the beach 

 after storms. 



Fam. 21. Saxicavidae, Swainson. 



Genus 2. Saxicava, Fleurian de Bellevue. 



Saxicava rugosa, L. Op. cit. iii. p. 81, v. pi. 51. f. .3 & 4. 



Common at low-water mark amongst the rocks in crevicea 



and holes in sandstone and shale, as well as inside empty 



limpet-shells and Balani. Often firmly adherent to its cavity 



by a byssus. 



Fam. 23. Pholadida, Gray. 

 Genus 1. Pholas, Lister. 

 Pholas Candida^ L. Op. cit. iii. p. 107, v. pi. 52. f. 2. 

 Karely found in shale at the Castle Rocks ; commonly met 

 with on the beach after storms, sometimes in a perfect con- 

 dition. 



Pholas crispata, L. Op. cit. iii. p. 112, v. pi. 53. f. 1. 

 Abundant in the soft shale and sandstone at East and West 

 Rocks, and especially opposite the castle. Occasionally the 

 siphons are observed protruding through sand which coats 

 some of the ledges. Young specimens are often cast ashore 

 on the West Sands in water-logged and decayed wood, whence 

 they are extracted by the sea-fowl. 



Genus 3. Xylophaga, Turton. 



Xylonhaqa dorsalis, Turton. Op. cit. iii. p. 120, 

 ^ ^ ^ v! pi. 53. f. 4. 



Not common; several living specimens occurred in the 

 wood of a submerged thorn tree. 



