30 Letters from J .MacGiWivvsiy, Esq. 



Among the excursions which I made was one of sixteen days' 

 duration to Broken Bay and Brisbane Water, chiefly for the pur- 

 pose of obtaining a small kangaroo, closely allied to H. Thetidis, 

 of which a skin had been shown me in Sydney. Although un- 

 successful in the main object of my search, I was yet much 

 pleased with the excursion as a reminder of former bush life and 

 a training for future work on the N.E. coast. Among other 

 matters of interest I may allude to the enormous accumulations 

 of dead shells of a large Area [R. 402] *, w^hich at first sight may 

 be mistaken for raised beaches. These heaps are often twenty 

 feet or more in depth and several hundred yards in length, co- 

 vered with a stratum of earth supporting the largest Casuarince, 

 This shell had for ages constituted the principal food of the 

 Aborigines, w^ho were once so numerous that a settler still alive 

 has seen 300 of their fighting men assembled at one time, while 

 at the present moment there are not more than ten in the district, 

 and in a few years the tribe will be extinct. Here also are some 

 of those magnificent " brushes,'^ portions of which remind one of 

 an Indian jungle. Eucalypti of enormous size, and gigantic 

 fig-trees form a canopy above, while below the dense underwood 

 is bound together into a tangled and almost impenetrable mass 

 by creepers and parasitic plants mixed up with cabbage-palms 

 and tree-ferns. A kind of churchyard dampness pervades the 

 atmosphere of these gloomy solitudes, and the silence is broken 

 only by the cooing of the wonga-wonga {Leucosarcia picata), or 

 the loud and startling note of the Psophotes crepitans. These 

 brushes are the haunts of the Menura and satin bird, also of se- 

 veral species of kangaroo. The dead logs harbour two kinds of 

 Helix [R. 386 and 388] f and numbers of coleoptera. One can- 

 not help noticing the powerful influence exercised by insects and 

 their larvse upon the destruction of fallen timber in these brushes ; 

 on the other hand, no sooner does a tree fall into the water than 

 the Teredo and a small crustacean [C. 183] efi'ect a lodgement, 

 and in a few months its internal structure resembles that of a 

 honey-comb. Having been provided with a light dredge which 

 could be worked by two persons (although my back has scarcely 

 even now recovered from the straining it received in consequence), 

 we made use of it on several occasions in some of the creeks and 

 also in the main channel, but the weather prevented us from 

 passing the surf in our frail skiff" and dredging in Broken Bay. 

 A very few shells, and only two kinds of Asteriada, were all that 

 we obtained. 



The best shell obtained by dredging in Port Jackson is Trigo- 

 nia pectinata, of which I have sent a fine series. It is exceedingly 



♦ J}'ca trepezizia, Desh. f Helix Georgiana and another. 



