1852.] LYELL BELGIAN TERTIARY FORMATIONS. 337 



(2.) St. Gilles. Fabrique d'eau forte (E. Map, fig. 3, PL XVII,, 

 and Section, fig. 8). 



Another locality where the upper Brussels sands immediately 

 below the Laeken beds are seen with the Nummulites l(2vigatus bed 

 at their base, is in the suburb called St. Gilles, at the Distillery " Fa- 

 brique d'eau forte," on the high-road to Waterloo. The fijssils which 

 I collected there, or which are in Captain Le Hon's cabinet, are first 

 the seventeen species to which an asterisk is prefixed in the preceding 

 list, and in addition, the two following : — 



Scalaria, allied to S. spirata ; perhaps a variety. 

 Coelorhynchus rectus, Agas. (found by M. Nyst). 



The bed {Nummulites IcEvigatus bed) on which the sands above- 

 described repose at the " Fabrique d'eau forte," is full of a prodigious 

 quantity of fish-teeth, much rolled, of the genera Lamna, Otodus, 

 MyliobateSj Coelorhynchus , and Edaphodon, mixed with fragments 

 of Asterias. 



Among the fossil teeth in Captain Le Hon's collection, found at this 

 spot, and in the same Nummulite-bed at several places in the neigh- 

 bourhood, I have recognized the following species : — 



Fossil Fish in the gravelly bed with Nummulites Icevigatus. 



Lamna elegans, Ag. 



Otodus obliquus ?, Ag. 



Pristis, resembling that figured in Dixon's * Foss. Suss./ pi. 10. fig. 6. 



Myliobates Dixoni, Ag. Dixon, pi. 10. fig. 2, and pi. 12. fig. 3. 



striatus, Ag. Dixon, pi. 12. fig. 2. 



Edaphodon Bucklandi. Dixon, pi. 10. fig. 21. 



Saurian from the Num. Icevigatus bed. 

 GaviaMs Dixoni ?, Owen, Dixon, pi. 12. fig. 24. 



A single tooth, much resembling the figure above cited (a Saurian 

 from the Eocene deposits of Bracklesham), was found by Captain 

 Le Hon with the fish- teeth. 



From the data supplied by Captain Le Hon respecting the relative 

 abundance of the Echinoderms and Molluscs in the Nummulites Icevi- 

 gatus bed at this point, and in some other adjacent localities. Prof. 

 Forbes infers the depth of the water to have been about 1 5 fathoms. 



I observed at the same spot at St. Gilles a remarkable proof of 

 the denudation of the underlying Eocene beds previously to the for- 

 mation of the Nummulites Icevigatus bed. A cast of Rostellaria 

 ampla in a siliceous sandstone accompanies the Nummulites, and on 

 some of the whorls (the shell itself having wholly disappeared) are 

 seen two species of Bryozoa {Escharina and another) adherent. The 

 small cells as well as their bases remain, and it is clear that they 

 originally covered the surface of the cast after the shell itself had 

 been dissolved. 



(3.) St. Gilles. Fort Monterey (F. Map, fig. 3, PL XVII.). 

 In the parish of St. Gilles, near Fort Monterey, in a pit not far 



