57 



well worthy of consideratioo whether exotic water weeds might not 

 be effectually introduced into some of the more rocky rivers with good 

 results, care being first taken to ascertain what water weeds will be 

 useful without becoming such a nuisance as the AnacharU alslnastrum, 

 or Canadian duckweed has proved itself in the English rivers, or the 

 common watercress in those of New Zealand. Mr. Gould quite endorsed 

 the Chairman's opinion as to the value of weeds as food producers for 

 the fish, but pointed out that, though beneficial to the fish, they were 

 frequently detrimental to the fisherman. Mr. W. E. Shoobridge men- 

 tioned that an indigenous grass-like weed had much increased in the 

 Derwent, between New Norfolk and the Styx, during the last few years, 

 but he much doubted whether any weeds could get a footing in the 

 upper streams, from the rapidity of the currents. 



Mr. Gould introduced to the notice of the Society a small series of 

 beautifully crystallized examples of three species of minerals, identical 

 in chemical composition, but differing in various physical characteristics, 

 such as system of crystallization, cleavage, &c. These were Rutile, 

 Anata.se, and Brookite, all of which had the same composition (Oxide of 

 Titanium, or Titanic Acid). 



The Rutile, Mr. Gould pointed out, presented a good example of 

 doubly geniculated crystals of the pyramidal system. 



The Anatase occurred in simpler forms of the same system, while 

 the Brookite belonged to a totally distinct system of crystallization, the 

 Rhombic, or Trimetric. 



The Butile has been found abundantly in a locality originally dis- 

 covered by Mr. James Smith. The other species occurred with it, but 

 only in rare specimens. 



Tito?? ic ^c«^ commands a high price at home for limited quantities, 

 from its yielding a rich colour for painting porcelain. Numerous patents 

 have also been taken out by Mr. Mushett, a metallurgist of repute, for 

 applying Titanic Acid to the oroduction of steel of superior quality. 

 Hitherto, however, Mr. Mushett does not appear to have achieved by 

 them a commercial success. 



This But He occurs at Clayton Rivulet, on the N.W. Coast of Tas- 

 mania, in a drift derived from the destruction of Metamorphic Rocks. 



Mr. Gould also exhibited specimens of Kyanite (a mineral sometimes 

 used as a substitute for sapphire) and of rubies and sapphires procured 

 from near the same locality. 



After further conversation, in which Mr, Grant, Mr, Giblin, Mr. 

 Abbott, and others took part, 



Mr. Justice Dobson, in proposing a vote of thanks to the donors of 

 presentations, referred especially to the contributions made to the 

 Museum, not only at the present meeting, but on former occasions, by 

 Mr. Gould. These presentations would remain with us as permanent 

 mementoes of Mr. Gould's discoveries, details of which were more 

 particularly given in the papers and proceedings of the Society. As to 

 the great presentation of the evening (the Moa bones), he (Mr. Dobson) 

 had some difficulty in expressing the pride and gratification with which 

 he regarded it, and in saying so, he was sure he only echoed the 

 feelings of every one present. It was indeed a noble gift, and one of 

 which even the British Museum itself might be proud. To Dr. Haast, our 

 warmest thanks were due for this invaluable addition to our Museum. 



Mr. Barnard, in seconding the vote, referred to the fact that a very 

 interesting and original paper by Mr. W. Colenso, on the Moa, appeared 

 in the Tasmanian journal of Natural Science as far back as 1843. lour 

 years before that period, Owen had read his celebrated paper on some 

 fragments of the bones of the Moa before the Zoological Society, 



The vote having been passed, the meeting terminated. 



