70 FOSSILS OF THE TACONIC SLATE. 



rig. 10. 



The slate in which this specimen was found is rather coarse, and somewhat unlike the 

 fine green taconic slate. It is not easily split into laminae, and hence it will be difficult to 

 obtain the fossils it may possibly contain. It was found in Brunswick, Rensselaer county, 

 b)' my friend Dr. Skilton of Troy. 



That the above fossil was the tube of an annelide, is of course suggested by the circum- 

 stance that animals of this class are found in this rock : the idea is in keeping with this 

 fact, and probably would not have been thought of independently. It is evident, however, 

 that the annelides yet discovered in the Taconic rocks were naked, or did not construct 

 tubes for their habitations ; so that it is not supposed that this relict was the tube of one of 

 the species which I have figured and described. 



Should no farther discoveries in fossils be made, the Taconic system will present a very 

 singular and remarkable condition: the animal kingdom being represented for along period 

 by a single fragment, and that fragment belonging to one of its obscurest families, yet not 

 the lowest in the scale of organization ; but the most striking peculiarities consist in the 

 remarkable forms here preserved, and the absence of all others which might serve to 

 connect them with the known parts of the series. The JVereites and congeners standing, 

 as it were by themselves, the sole representatives of one of the kingdoms of nature ! Sub- 

 sequently each geological period or era had many forms, typical of many divisions of the 

 animal kingdom. But here, the entire absence of those forms which become so abundant 

 at the very commencement of the succeeding system, is, to say the least, extremely in- 

 teresting. However, so strange an anomaly is not to be admitted at once ; although for 

 many years these rocks have been diligently examined, without furnishing a single 

 mollusk. 



I would here remark, that in consequence of the similarity of the taconic slates and 

 some of the rocks of the Champlain group, fossils have been occasionally presented in 

 their matrix, when it was doubtful to which system they belonged. In these cases I have 

 invariably visited the spot, for the purpose of determining the exact position the fossil 

 occupied ; and, in all cases where they were testacea, they were found in the New-York 

 system. 



