Geological Society. 147 



brown, and fawn-colour, the latter occupying the external edge of 

 the feathers, and the black and brown formmg alternate circular 

 markings on each feather ; throat, neck, chest and flanks dull fawn- 

 colour ; the feathers of the neck and chest blotched with brown ; 

 flanks marked with the same colour, assuming the form of bars ; tail- 

 feathers, which are almost invisible, marked the same as the back ; 

 centre of the abdomen and the under tail-coverts bufFy white, with- 

 out spots or markings ; irides straw-yellow ; bill yellow, passing into 

 black at the point ; feet greenish yellow. 



Total length, 41 inches ; bill, {-^ ; wing, 3^ ; tarsi, |. 



The above are the measurements of an old male. 



Hub. Plains of the interior of South Australia. 



DiiFers from P. torqiiatus in its smaller size, in the absence of the 

 coUar, and in the almost total absence of tail. 



Mr. Gould also brought befoi'e the notice of the Meeting a new 

 species of Megapodius, from the north coast of Australia, which he 

 characterized as M. Tumulus, and read a very interesting account of 

 its habits, which tends to confirm the opinion he had previously ex- 

 pressed, that Megapodius Talegalla and Leipoa form part of one great 

 family of birds, whose range will be found to extend from the Phi- 

 lippines to Australia. 



Megapodius tumulus. M. capite, et cristd saturate cinnamomino- 

 fuscis ; nucha, et corpore subtus saturate cinereis ; dorso, alisque 

 cinnamomino-fuscis ; tectricibus cauda, crissoque saturate casta- 

 nets ; pedibus permagnis. 



Head and crest very deep cinnamon-brown ; back of the neck and 

 all the under surface very dark grey ; back and wings cinnamon- 

 brown ; upper and under tail-coverts dark chestnut- brown ; tail 

 blackish brown ; irides generally dark brown, but in some specimens 

 light reddish brown ; bill reddish brown, with yellow edges ; tarsi 

 and feet bright orange, the scales on the front of the tarsi, from the 

 fourth downwards, and the scales of the toes dark reddish l)rown. 



Total length from 15 to 17 inches ; bill from li to 1^ ; wiug from 

 9| to 10 ; tail from 4 to 4| ; tarsi from 2| to 3^. 



Hub. Cobourg Peninsula, on the north coast of Australia. 



GEOLOGICAL. SOCIETY. 



Feb. 23, 1842. — A memoir was read, entitled, " Report on the 

 Missourium now exhibiting at the Egyptian Hall, with an inquiry 

 into the claims of the Tetracaulodon to generic distinction," by- 

 Richard Owen, Esq., F.G.S., &c. 



Mr. Owen proceeds to consider the species of animal to which 

 the skeleton is to be referred. It was, he says, a mammiferous 

 animal, and while the anterior extremities disprove the existence 

 of clavicles, they establish that the fossil belonged to the Ungu- 

 lata. The enormous tusks of the upper jaw further show that 

 it was a member of the proboscidean group of Pachyderms, ana that 

 the molar teeth prove it to be identical with the Tetracaulodon or 

 Mastodon giganteum. With respect to the horizontal position of the 

 L2 



