sericea, Soweiby, Lymlesma pulchellurn, Hall, Orthoceras lamellosum, Hall, and 

 species of Orthis and Sirophomena, etc. It is immediately overlying this exposure 

 that we find cropping out several bands of yellow-weathering: magnesian lime- 

 stone, probably similar to those found at the St. Anne River, Montmorenci. In 

 these bands are several specimens of Conularia Trentonensis, Hall, Orthoceratidae 

 and Cahjmenc callicephala, Green, etc. The beds here dip at a small angle to 

 the east, across the river, where, a little above and in the vicinity of the rapids, 

 beds overlying these are seen which present new forms such as Modiolopeis 

 modiolaris, Conrad, M. anodontoides ? Hall, another Jlodiolopsis, probably a new 

 species, associated with Avicula insueta, Conrad, and a few graptolitic fragments. 

 Following the line of outcrop down the river we come to Cummings' Bridge 

 where a very interesting deposit occurs. Here the remains of Triarthrus spnnosus, 

 (Billings), are abundant, some very fine and probably perfect specimens having 

 been obtained. T. Becki, (Green), also occurs there, and with it very numerous 

 specimens of Orthoceras lamellosum of Hall, which are often found completely 

 pyntized. The trilobites also are often coated over with pyrites. 



Graptolites occur in this deposit, but not in a very good state of preserva-. 

 tion. With these, are also associated numerous minute linguloid shells of the 

 genus Leptobolus, most of which are referable to L, insiynis of Hall, (24th Annual 

 Report, N.Y. State Cabinet). 



The total thickness of the exposure is about ten feet, the beds presenting 

 much fission and crumbling. The next deposit worthy of note, and but recently 

 noticed, is that which lies beyond the track of the St. Lawrence and Ottawa Rail- 

 way, to the north-east of the last mentioned deposit. The chief characteristic 

 of this is the abundance of graptolites. Very little has been done here as yet, and 

 ith&iij'\Q\dGd Graplolithus pristis, (Hisinger?) G. flaccidus, (Hall.) G. annecians 

 {Walcott). G. Sagittarius, (Hall). G. quadrimiicronatus, (Hall). 



The graptolites in this bed are in a very perfect state of preservation, their 

 condition greatly facilitating the identification of the different species. 



Exposures of more or less importance also occur in the village of New 

 Edinburgh and on the Montreal Road. At New Edinburgh, during the excava- 

 tions rcade for water-works purposes, some very interesting forms were obtained 

 by His Excellency Lord Lome, among which may be mentioned Ceraurus 

 pleurezanthemus, (Green). 



On the Montreal Road, about two miles from the Rideau River, and resting 

 almost at the summit of an axis of disturbance in a Trenton anticlinal, we 

 find another exposure some fifteen feet thick, consisting chiefly of brown, brittle, 

 and highly clcacable rock, but very unpromising as to fossils. 



Now, taking these exposures severally, in order, and observing their strati- 

 graphical arrangement as constituting different horizons, marked respectively by 

 difterent sets of fossils, and looking at them likewise in their lithological charac- 

 ter, we obtain a series of beds, though scattered about, giving us a total thickness 

 of probably not less than forty feet. 



Notes on Some of the More Interesting Fossils from the Ottawa Beds. 



1. Conularia Trentonensis, (Hall). Several specimens of this Pteropod have 

 been found, as mentioned above, in the deposit at the Rifle Range. It was at 

 first thought to be C. Iludsonia of Emmons, but after referring it to Principal 

 Dawson, he writes thus : — "After careful examination I cannot make your Con- 

 ularia distinct from Trentonensis. There are two species described from the 

 Utica, C. Iludsonia, of Emmons, and another, but yours does not agree with 

 either." This species has not been previously recorded as occurring in the Utica 

 Slate either of Canada or of the United States. 



2. Triarthrus spinosus, (Billings.) Very fine and perhaps perfect specimens 

 of this species have been found in the Cummings' Bridge deposit. Some new 



