386 Geological Society : — 



very large, the part concealed by the jaw being exceedingly long. 

 One tooth, exposed in its whole length by the breaking away of the 

 bone, measured 6-4 inches, of which the crown formed 2-6 inches. 

 June 9th, 1869.— Sir R. I. Murchison, Bart., F.R.S., V.P.G.S., in 



the Chair. 

 The following communications were read : — ■ 



1. " Notes on the Sutherland Gold-fields." By the Rev. J". M. Joass. 



2. " Observations on the ' Nuggetty Reef/ Mount Tarrangower 

 Gold-field." By Dr. G. H. F. Ulrich, F.G.S. 



The author commenced by indicating the position and characters 

 of the so-called " Nuggetty Reef," which is situated about 2| miles 

 N.N.¥. of the little town of Maldon, about 87 miles N.W. of Mel- 

 bourne, and consists of two strong quartz veins, separated by a mass 

 of bluish-grey metamorphic sandstone. In certain places the 

 " reef" is cut transversely or obliquely by granite bars or veins, of 

 which the author described four, and stated that, although some of 

 them are, and all piobably have been, connected with the main mass 

 of granite, they present rather the appearance of zones of impreg- 

 nation than of intrusive dykes — there being no line of separation 

 between the quartz rock and the granite, but felspar and black mica 

 make their appearance in the quartz, and gradually increase in 

 quantity until the granite band is formed. The author noticed the 

 following minerals as associated with the gold in the " Nuggetty 

 Reef:" — Iron pyrites, arsenical pyrites, magnetic pyrites, copper 

 pyrites, galena, zinc-blende, and a compound of gold and bismuth, 

 to which he gave the name of Maldonite. 



3. " On the Caratal Gold-field." By Dr. C. Le Neve Foster, F.G.S. 

 The author stated that the Caratal Gold-field is situated about 



100 miles south of the Orinoco, at a point about 75 miles above 

 its principal mouth. The rock of the district is chiefly gneiss, with 

 some mica-schist, hornblende schist, and granite. The gold- occurs 

 in four ways : — 1, in lodes, veins, &c. ; 2, in alluvial or "placer" 

 diggings ; 3, in red earth or " Tierra de flor ;" and, 4, in gravel and 

 sand of river-beds. The mode of occurrence of the gold in these 

 different places, and the variousvprocesses employed in collecting it, 

 were described by the author, who estimates the quantities of the 

 precious metal obtained in the Caratal district as follows : — 

 In 1866 15,587 oz. 



1867. 30,142 oz. 



1868 (9 months) . . 22,481 oz. 

 The greater part is obtained from the lodes. 



4. " On the Geology of Guyana in Venezuela." By Ralph Tate, 

 Esq., Assoc. Linn. Soc, F.G.S. 



The author prefaced his remarks by pointing out the leading phy- 

 sical features of Guyana in Venezuela, and by alluding to the Geo- 

 logy of Venezuela to the north of the river Orinoco, as determined 

 by Mr. Wall. 



Mr. Tate has ascertained the existence of an extensively deve- 

 loped metamorphic series, consisting of felstones, talc' schists, 

 quartzites, gneiss of great variety, hornblende slate, and amphibole 



