*^'^''' 1 Chapma'!<!, Impression of Fi'uif. of Casiiarina. <S9 



ON AN IMPRESSION OF THE FRUIT OF CASUARINA 

 OR SHEOAK IN THE NEWER BASALT OF VIC- 

 TORIA. 



(With Plate.) 



By F. Chapman, A.L.S., Palseontologist to the National 

 Museum, Melbourne. 



(Read before the Field Naturalists' Club of Victoria, 14th Sept., 1914.) 



A FEW weeks ago a block of basalt lava from Yandoit Hill was 

 submitted to the Museum for determination by Mr. Thomas 

 Smith, of Newstead. Mr. Smith writes, under date 13th July, 

 1914, as follows : — 



" I am sending an impression on a piece of volcanic stone 

 that was picked up by my uncle many years ago on the northern 

 slopes of Yandoit Hill. In the alluvial under the basalt of the 

 hill impressions of leaves have been found, and some of these 

 which I saw I remember as having a likeness to Banksia leaves 

 and the rather long and narrow leaves of eucalyptus ; but I 

 was too young at the time, and so cannot say for certain. The 

 stone with the impressions which I am forwarding was, how- 

 ever, picked up on a spot beneath which there must be a con- 

 siderable thickness of basalt, so that the organisms that formed 

 the impression must have existed after at least the first eruption 

 of the old volcano." 



At first sight the impression in this piece of lava was rather 

 puzzhng. It certainly seemed organic, on account of its regular 

 marking. No animal structure suggested itself as likely to 

 have formed this impression. My attention was thus natur- 

 ally directed to the plants. The only plant structure which 

 could have formed the impression appeared to be that of a 

 fruit ; and, since Mr. Smith mentioned in the letter quoted 

 that leaves like Banksia and Eucalyptus had been found in the 

 alluvial under the basalt of the hill, I thought of the cones of 

 Banksia. Upon taking impressions of these cones the result 

 was negative, in that the impressions of the cortical scales 

 were lozenge-shaped. Then Casuarina suggested itself, and on 

 taking impressions of the fruit of this genus the likeness was 

 seen to be perfect. 



It may here be noted that plasticine offers a ready and 

 effective medium for obtaining impressions of fossils, and this 

 material was used in the present instance. The fruits first 

 examined for comparison in this case were from Casuarina 

 stricta, or quadrivalvis, by which latter name, although not the 

 older, it seems more generally known. In order to arrive at 

 a more precise determination, I examined a series of fruits at 

 the National Herbarium, with the result that the impression 

 was seen to be nearest to that formed by Casuarina stricta, the 



