SUn-FiiSSII, CKUSTArKAXS KTHEKMIm;K AXI' McClMJ-OCH. 5 -. 



to eio^hteeii feet, and of the tough clays coiubined fi-oiii eight to 

 twenty-five feet. Tlie apfjearance of the few sub-fossil Crus- 

 tacea seen from this deposit leads us to believe they came from 

 the bottom tough yellow clay ; we have not seen any remains in 

 calcareous cement nodules as desci'ibed bv Mi-. Wintle. 



•4. Eutntiu-e Brixhniii' liiuer, Mori'hm Jloi/. — Mr.. I. H. Stevens, 

 Ins{)ector of Fisheries, Bi'isbane, informs us that the sub-fossil 

 Crustacea fi-om this locality were obtaineii from the New Chan- 

 nel Cutting at the entrance to the Brisbane Rivei-, now forming 

 the nrain wateiway. 



The cutting was dredged through a large bank about half a 

 mile wide, a continuation of Fishei'man Island. Previous to the 

 dredging opei-ations tlie bank was covei-ed with about two feet 

 of water at ordinary low-water spring tides, but at verv low 

 tides parts of the bank were quite exposed ; the depth of the 

 channel is now twenty-eight feet. The specimens collected 

 came from a depth of about sixteen feet from the surface in 

 sand and mud. Mi'. Stevens considers the bank had evidenth' 

 accumulated through the deposition of sediment from the flood - 

 waters of the Bi'isbane Hiver. 



The aspect of these t'rustacea is quite different from tliose 

 obtained farther noi'tli and north-west. The matrix is a, hard 

 ochre-coloured, slightly calcareous mud. Dr. Anderson also 

 submitted portions of these to a qualitative analvsis, and informs 

 us that: — '* Portions of the exoskeleton, cleaned jis (■om[)letely 

 as possible from adhering matrix, were treated with hot dilute 

 hydrochloric acid. A fragiiient of a clieli[)ede became con- 

 verted into a white, soft, amorphous substance, which readily 

 carbonised on heating. Portion of the carapace was attacked 

 less readily and left st)me inorganic residue, but the presence of 

 organic matter was proved as before. These experiments 

 indicate that there is little or lu) petrifaction ; thei'e is some 

 infiltration of mud or clay, particularh- in the case of the less 

 dense carapace, and it is apparent that, as we should expect, 

 the pi'oportion of organic matter is lower than in a recent speci- 

 men (tested for compai'ison), but a considerable amount of 

 chitin still persists in the skeleton." 



