16 Sedimentary Formations 
have very extensively collected from the region along the Yass 
and Murruinbidgee Itivers (in continuation of my earlier re¬ 
searches), and have had the opportunity of being accompanied 
in 1870 by Mr. Jenkins, of Yass, whose acquaintance with the 
pahTontological treasures of that neighbourhood is very great,— 
it has been my good fortune to line! the missing Calceola and 
numerous Trilobites alluded to in the preceding extracts from 
De'JConinck’s admirable Rccherekes.” At present I am unable 
to submit these Yass fossils for description. 
Jn addition to Calceola (which occurs also at Mount Eromc, 
County Phillip) I have been also able to satisfy my friend that 
Recpptaculites Neptuni also exists in Now South Wales, as well 
as II. Australis , which was sent by me to the late Mr. Salter and 
figured by him in the “ Decades of Organic Remains of the 
Geological Survey of Canadaf in comparison with R. Occi¬ 
dental is syn. of R. Xeptuni (See Decade 1, pp. 45-1-7, pi. x, figs. 
1-10). (See Appendix XVII before cited.) 
It is true that Mr. Salter regards the R. Australis as Upper 
Silurian, and rightly associates it with Tentaculites, Pavosites, 
Pentamerus, Orthoceras, Trochonema, Khyneoncdla, &c., which 1 
discovered in the south-western district of Maueero in 1851-2, 
and also that R. Xeptuni came from between Wellington and 
Molong ; and that the actual limits of the Upper Silurian and 
Devonian formations have not yet been accurately defined. But 
when wo find such a genus as Xiso represented in a Palaeozoic 
formation, as is the case with the Devonian of New South Wales, 
and notice how frequently of late paleontologists have been 
obliged to admit the occurrence of genera and sometimes of 
species of acknowledged younger formations in those of more 
ancient date — as anticipatory of future existences — it maybe well 
believed that Recepfaeulifes may be generically known to such 
double relations as the Silurian and Devonian. {See infra , p. 07.) 
“ C’est pour la premiere fois,” says Do Ivon inch,” quo la pre¬ 
sence dtt JYiso est sign alee dans les terrains Paleozoiques, et il 
faut remonter jusqu ’an terrain Tertiaire pour cn retrouver do 
nouveau les traces; copeudant mon savant et excellent ami M. 
Nyst, sans contredit un des moillours conchyliologistes dc 
l’epoque, que j’ai consults a eet dgard, croit pouvoir declarer avee 
moi, qu'il it existe pas une difference sujjisante enfre les carac - 
teres yen era ux de Vespece Devonicnne et ccux dc Vespece Tertiaire 
pour ne pas considerer Tune et Vautre commc gencriquemcnt 
ideniifjucs 
I may add here, that some years since, I sent to II. M. Jenkins, 
Esq., i'.Gr.S. (when Curator of the Geological Society), a 
species which he considered to he a Lcpralia , which was bedded 
in the limestone of Cavan on the Murruinbidgee and in the same 
