DISTRIBUTION OF SOUTHERN HIGH-LATITUDE MOLLUSCA 69 



True Laevilitorina ranges from Patagonia to the subantarctic islands of New Zealand, but is replaced 



on the New Zealand mainland by Zelaxitas. Here again the Australian ' Laevilitorina ' mariae Tennyson 



Woods, 1876, requires investigation. The distribution of the Laevilitorinids is again suggestive of an 



eastern subantarctic drift from the American Quadrant. 



iV 



■V 



V 



.c^)J>7 \ ^7 



\ 



Fig. C. Distribution of Antarctic and Subantarctic Trochoids. Calliostomatinae bounded by double lines, Stomatellinae by 

 a single line. A = Antimargarita. C = Calliostoma. C (M) = Calliostoma (Venustas). F = Fahimargarita. M ' = Margarella. 

 P = Promargarita. Pz = Photinula and Photinastoma. T = Tropidomarga. V=Veniistatrochns. 



Family Naticidae 



If I am correct in assigning most of the southern high-latitude Naticoids to the boreal genus 

 Amauropsis, there is no doubt that the continuity of the west coast of the Americas indicates the former 

 route. Of the remaining Naticoid genera, Falsilunatia has most in common with northern Limaha, 

 Tectonatica is a Mediterranean Pliocene genus, Sinuber ranges from the Falkland Islands and South 

 Georgia to the South Shetland Islands and eastwards to Kerguelen and the Ross Sea, and Prolacuna is 

 apparently restricted to deep water of Antarctic occurrence, extending from the Davis Sea to the Ross 

 Sea. The American route is again indicated. 



