THE VICTORIAN NATURALIST. 1 5 



on that account was asked to report upon it. It certainly some- 

 what resembled a hardened mushroom, consisting of a stalk and 

 an expanded rap-like portion ; but appearances are often very 

 deceptive, and in this case it proved to be so. 



The specimen was found at Bridgewater, Western Victoria, 

 about a mile from the local hotel, between the beach and the 

 cliffs, on a kind of irregular path frequented by numerous visitors. 

 The whole is of a brownish-black colour, and the cap-like portion 

 is roughly round, measuring 4)^ in. in diameter, convex and 

 broken up into numerous blunt tooth-like parts, somewhat re- 

 sembling the overlapping scales of a pine cone. On the under 

 surface it is slightly concave and relatively smooth compared with 

 the upper, which has evidently been the side most exposed to 

 weathering. The stalk is inserted in the centre rather obliquely, 

 more or less compressed, and tapering slightly towards the base, 

 being a little over 3 in. in length and 1-13^ in. across. It is 

 very rough, and has a dark ashy-grey aspect. The whole weighs 

 8^ ozs., and was certainly of a sufficiently striking character to 

 be picked up as a ' curio.' In order to get at its true nature, it 

 is essential to see the interior and make, say, a longitudinal section 

 right through the centre of it, but as the finder wished it to be 

 preserved intact, that could not be done. However, by a lucky 

 accident, the stalk was broken across near the base, and the 

 woody core was revealed, of a creamy colour, while the outside 

 was dark-coloured and very irregular. Professor Gregory, of 

 the Melbourne University, to whom the specimen was sub- 

 mitted, had determined it as a woody callosity, and not a fossil 

 at all. 



I had already examined the woody portion under the micro- 

 scope, and found it to consist, not of fungus filaments, but of 

 cellular tissue. Hence the specimen could not possibly be a 

 fungus. A small portion was also thoroughly soaked with iodine 

 and then treated with sulphuric acid, when it became of a deep 

 blue colour, thus giving the well-known cellulose reaction. This 

 proved that the substance had neither become petrified nor 

 fossilized, but was perfectly normal, In some portions of the 

 woody tissue there was found a perfect network of fungus 

 filaments — elongated, branched, and closely septate. These 

 filaments were the only traces of fungi found, and were pro- 

 bably parasitic. Thus the specimen turned out to be interesting 

 — not, however, as a petrified mushroom, but as one of those 

 peculiar excrescences found on various trees, and known 

 as "burrs," "gnaurs," "wens," or "exostosis." These ex- 

 crescences are usually very irregular and woody, with gnarled 

 and warted surfaces. They occur on a number of different 

 trees, very commonly on the elm, and vary in size from that 

 of a pea to that of a cocoa-nut or larger. It has been as- 



