GEOLOGY. 335 



my Quincy specimens, we can hardly doubt that the original specimen of Par. 

 Harlani came either directly or through the drift scattered in the vicinity, 

 from the same fossiliferous belt. Thus it appears that this vagrant fossil, so 

 long without a local habitation although not without a name, has at length 

 been restored to its native seat, where it takes a prominent place in the 

 dynasty of ancient living forms that marked the earliest paleozoic history of 

 New England. 



In this connexion I find a remark in Barrande which, besides being his- 

 torically curious, has an interesting bearing on the specific affinities of the 

 fossil. He observes : " We see in different collections and especially in that 

 of the School of Mines and the British Museum, under the name of Par. 

 Harlani, from the United States, a cast of a Trilobite which appears to us to 

 be identical with P. spinosus, of great size, such as found at Skrey, in 

 Bohemia." The cast here referred to, like that used in my comparison with 

 the Quincy fossil, was doubtless one of the series of plaster copies prepared 

 by Dr. Green to accompany his monograph. Its agreement with P. spinosus 

 harmonizes well with my own observation, already stated, of the close 

 resemblance between the Quincy fossil and this Bohemic species. 



The occurrence of well preserved fossils among rocks so highly altered, 

 and so contiguous to great igneous masses, as are the fossiliferous. slates of 

 Quincy, may well encourage us to make careful search in other parts of New 

 England, where heretofore such an exploration would have been deemed 

 useless. Although we cannot hope to build up the geological column of 

 New England from the protozoic base just established to the carboniferous 

 rocks, supposing ah 1 the intervening formations to be represented in this 

 re gi on -we may at least succeed in determining by fossils hereafter discovered, 

 some of the principal stages in its structure, and in thus relating its strata 

 definitely to the great paleozoic divisions of Appalachian G-eology. 



FOSSILS FROM THE XEW RED SAXDSTOXE OF PEXXSYLVANIA. 



At a meeting of the Philadelphia Academy of Natural Sciences, April, 

 1856, Mr. Lea read some notes from a paper on the new red sandstone forma- 

 tion of Pennsylvania, and stated that he had, during an excursion last sum- 

 mer, found in the dark shales of that formation, near Phoenixville, on the 

 Schuylkill, the tooth of a sauroid reptile. 



On comparing this tooth with Ckpsysaurus Pennsylvamcus, which he had 

 described from the same red sandstone formation in Lehigh county, it will be 

 found to differ very widely. The edge is not serrate on any part like that 

 genus, nor is it so large or so attenuate. The form, too, is more compressed. 

 It differs from the teeth of Bathygnathus lorealis, Leidy, from the new red 

 sandstone of Nova Scotia, in size, being smaller and being more attenuate, 

 as well as having a trenchant smooth edge and not a serrate edge. It is 

 about the size and approaches the form of Professor Owen's figure of 

 Labyrinthodon. 



Mr. Lea also stated, that in the greenish and blackish shales of the same 

 locality he found two species of Posidonia, which genus is so characteristic of 

 this portion of the formation and existing in immense quantities. As they 



