334 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



" The land shells from there were from the forested valley of the 

 river, where they are usually found under decayed tree-trunks, but 

 sometimes in the open. 



" The E,io Marazzi flows into the head of Useless Bay. The fresh- 

 water shells fi-om this river were taken about two miles inland, where 

 it is perfectly fresh." 



The following notes on the physical features of the island have also 

 been furnished by Capt. Crawshay :-^ 



"The shores of Tiei'ra del Fuego afford a weird and fascinating 

 study, for wind and wave have worked extraordinary results. 

 Common objects are the bones of whales, carcases of sea-lions and 

 guanacos, ships' boats, spars, rudders, and other wreckage, tree- 

 trunks, and endless odds and ends of timber in general. 



" The line of the last high tide is marked by huge masses of sea- 

 weed, with quantities of mussel- and limpet-shells. The prevailing 

 character of the beach in Admiralty Sound is grey shingle, with 

 stretches of large, round, water-worn stones, similar to those of the 

 British coast. In San Sebastian Bay, on the Atlantic side of the 

 island, the sea recedes an immense distance at low tide, laying bare 

 miles and miles of muddy sandflats. There I found several shells 

 which do not seem to occur on the opposite side of the island. Shells 

 are to be seen inland in Tierra del Fuego, on the surface and below 

 it, on the downs some 200 feet above the sea, both on the east and 

 west coasts of the island, thrown up by the burrowing Ctenomys, but 

 whether these represent the work of Indians in bygone times or 

 natural sea-deposits, I am not prepared to say. The shells thus 

 thrown up are almost invariably limpets." 



I. Marine Species. 



1. Trophon Geversianus (Pallas). 

 Hah. — Bio McClelland, west coast of the island. 



2. Trophon MURiorFORMis (King). 



Hub. — Bio McClelland, Useless Bay, west coast of the island. 



3. AcANTHiNA CALCAR (Mai'tyn). 

 Hah. — Bio McClelland and Admiralty Sound, west side of the 

 island. 



4. BULLIA SQtJALIDA (King). 

 Bullia sqnalida. King: Beeve, Con. Icon., vol. iii, pi. iv, fig. 26. 

 Hub. — San Sebastian Bay, east coast of the island. 



5. Natica atrocyanea, Philippi. 

 Natica atrocyanea., Philippi : Conch. Cab., p. 53, pi. viii, fig. 7 ; 

 Abbild., vol. ii, p. 41, pi. ii, fig. 1 ; Tryon, Man. Conch., vol. viii, 

 p. 37, pi. xiv, fig. 21. 

 Hab. — San Sebastian Beach (Crawshaj-) ; Straits of Magellan 

 (Philippi). 



It is curious that the outer cretaceous coating of this shell is liable 

 to be dissolved, leaving the deep purple under-layer exposed. 



