66 THE VICTORIAN NATURALIST. 



from which it was derived, as they are seen in the pebbles, and 

 pieces of quartz occur in the conglomerate. 



At one place an irregular mass, and a sheet running along a 

 joint, occur, composed of a fine-grained crystalline rock, appa- 

 rently intrusive in the conglomerate. This rock is scarcely at all 

 decomposed, but broken into small pieces in a manner similar to 

 that produced by great pressure. 



At its southern edge the conglomerate passes under the newer 

 volcanic rock of the plains. At one place the volcanic rock 

 appears to have flowed up an old valley in the conglomerate. 

 The present creek has cut through it again, showing at one place 

 the conglomerate at the bottom of the valley and on the ridge, 

 but volcanic rocks remaining on both sides at intermediate 

 levels. 



The age of this conglomerate is doubtful. On the geological 

 survey maps it is marked as oolitic, with a note that it is 

 probably of the age of the mesozoic coal measures. Mr. Selwyn, 

 in his " Geology of Victoria," speaking of the Upper Palaeozoic 

 rocks, mentions several localities in which conglomerates occur, 

 including this one, and expresses an opinion that this and the 

 more easterly ones are older than the western ones. The 

 presence of the quartz veins, which do not occur in the Bacchus 

 Marsh conglomerates, is also evidence in favour of greater age, 

 though these may be only a local development. In the absence 

 of any organic remains it would be difficult to refer this formation 

 to any particular age. 



The total difference of level of the highest and lowest places 

 at which I observed this conglomerate is 760 feet. This cannot, 

 however, be taken as representing its thickness, for though the 

 sandstone, in which the bedding is plainest, appears to be 

 horizontal, the coarse conglomerate would need a steep slope for 

 its formation, and could accumulate on a considerable slope. 



I have not been able to visit the more northern localities in 

 which the conglomerate occurs, but it would be interesting to 

 know their relation to this part and the levels at which they 

 occur. A further examination of the whole formation is needed 

 to determine the direction of the range from which it was 

 derived and its relations to the other rocks, particularly the 

 granite and trap rocks of the vicinity. 



SOME TRANSFORMATIONS OF AUSTRALIAN 

 LEPIDOPTERA. 

 By James Lidgett. 

 The present paper embraces the life-history of two species of 

 Victorian moths, both of which are fairly numerous, although the 

 former — Mnesampela privata — the most abundant, is difficult to 

 procure ; the latter — Nyctimera arnica — being easily procured. 



