.WTAKl Til A. 287 



position between the Annulate worms and the terrestrial Arthro- 

 pods. It is interesting to note that only recently this form has 

 been discovered in India, so that it is now restrictedly distributed 

 over all the main remnants of Gondwanaland. Across this area 

 we can well imagine the migration of that primitive reptile — 

 Sphenodar — to its future isolated home — Xew Zealand and 

 neighbouring islands, there to persist long after its relatives in 

 other parts had disappeared'. Xot later than early Jurassic 

 times we see the breaking up of the Indo-African portion of 

 Gondwanaland — the ancient Lemuria — and probably a series of 

 insular areas stretching from Madagascar to India. 



In Cretaceous times it would seem that the continents had 

 much the same configuration as that which now characterises 

 them, but South America and Australia were still linked up with 

 Antarctica. In this way the Diprotodont Marsupials evolved in 

 one area migrated to the other across an Antarctica which, as we 

 have already seen, enjoyed a much milder climate than the 

 present even into Tertiary times. This bridge between South 

 America and Australia may have been retained even into early 

 Tertiary times. 



For more definite mapping in of the various continental 

 ma>ses during Mesozoie and early Tertiary times we require 

 information other than that now accessible to us, and that we 

 may reasonably hope to acquire as the result of scientific investi- 

 gations in Antarctica. 



TSUMEBITE : A NEW MINERAL.— A few months ago 

 Karl Busz described in the Festschrift Deutsch. Naturforsch. 

 Aertse ( 1912, pp. 182-185) a ne w lead copper phosphate from 

 German South-West Africa. The mineral is found in the form 

 of small emerald-green monoclinic crystals, with cerussite and 

 chessylite, on snow-white calamine, together with reddish brown 

 dolomite, in the Tsumeb mines, Otavi. The specific gravity of 

 the new mineral was given as 6.133. Independently Rosicky 

 described in the Zeitschrift fiir Kryst. Min. ( 1912, pp. 521-526) 

 under the name Preslite, what was afterwards admitted to be 

 the same mineral, observed in small emerald-green crystals 

 associated with chessylite, cerussite, calamine, and dolomite. 

 The crystals were described as imperfectly developed, and 

 appared to be orthorhombic with complex twinning. To each 

 description an analysis of the new mineral was appended : — 



Busz. Rosicky. 



Lead oxide 63.77 65.09 



Copper oxide I *-79 II -97 



Phosphorus pentoxide 12.01 10.26 /Tv^ 



Water 12.33 — Ay OS ^o 



I 8R A R ^ 



