270 Ti'ansactions. 



15. Diplodon websteri, Simpson. 



It is the opinion of the Rev. Mr. Webster* that I was not 

 correct when I stated that I considered the above species as a 

 D. menziesi in which the nodulous sculpture is developed to the 

 highest degree. But we do find very interesting stages of 

 nodulous development. My assertion is based on facts, and 

 not on imagination. Webster seems to overlook the fact that 

 we have a form of Diplodon which stands very near D. websteri 

 — this is D. aucklandicus, Gray, which is considered by Simpson 

 as a synonym of D. menziesi, and I have already stated that 

 I accept his treatment of the two species. f In fact, the auck- 

 landicus form of D. menziesi and D. websteri are found living to- 

 gether ! I have specimens of the former with the nodules so 

 much developed that they approach Simpson's species very 

 closely. The hinge, thickness of the valves, and brilliancy of 

 the nacre are very variable in the genus, greatly influenced by 

 the surroundings — the condition of the bottom, the quality, 

 quantity, and mode of movement of the water. I consider D. 

 websteri as a good subspecies of Z). menziesi. 



'- 16. Rochefortia donaciformis, Angas, sp. 



Mysdla donaciformis, Angas, Proc. Zool. Soc, 1878, p. 863, 

 pi. 54, fig. 13. Bochefortia donaciformis, Angas : Hedlev, 

 Proc. Linn. Soc. N.S.W., 1902, pi. 1, figs. 10-14. 



A few valves were obtained by Captain J. BoUons when dredg- 

 ing in 18 fathoms, Port Pegasus, Stewart Island. They fully 

 agree with the diagnosis, the figures, and with specimens in my 

 collection from South Australia. 



17. Lima sydneyensis, Hedley. 



lAma brunnea, Hedley, Proc. Linn. Soc. N.S.W., 1901, p. 21, 

 pi. 2, figs. 7-9 ; non Cooke, 1886. L. sydneyensis, Hedley, I.e., 

 1904, p. 200. 



Mr. A. Hamilton, Director of the Colonial Museum, sent some 

 shells, collected by the late Mr. C. Traill, to Mr. C. Hedley, and 

 he wrote, under date the 9th July, 1904, that the above-named 

 species was amongst the lot — one of the rarest shells in Port 

 Jackson. It is at the special request of Mr. Hedley that I pub- 

 lish this note. 



* Trans. N.Z. Inst., vol. xxxviii, p. 311 

 t Trans. X.Z. Inst., vol. xxxvii, p. 234. 



