Geological Society. 115 



the Crags, and four of them new to science. A remarkable low- 

 crowned, but broad, lower carnassial tooth from the Norwich Crag of 

 Bramerton is referred to the genus Lutra, and named specifically 

 L. Reevei. All the other specimens noticed below are from the 

 nodule-bed at the base of the Suffolk Red Crag, and the first 

 four of them are in the possession of Mr. E. C. Moor, of Great 

 Bealings. A right ramus of a lutrine lower jaw, differing from 

 the common Otter in having the hinder fangs of the premolars 

 much larger than the front ones, and agreeing in this particular 

 with the Lutra dubia of DeBlainville, is referred to the latter 

 species. A humerus of a Seal, most nearly resembling that of 

 Phoca vitulina, but of smaller size and more slender proportions, is 

 called PJiocn Moori. Another Seal's humerus, having a peculiarly 

 triangular shaft, is thought to belong to the Phocanella minor of 

 Van Beneden. A maxiUa with three teeth, evidently belonging to 

 the genus Trogontherium, but of smaller size than the Trogontherium 

 Cuvieri, is believed to represent another species, and is named 

 T. minor. The ziphioid rostrum in the Ipswich Museum, which 

 received from the E.ev. H. Canham the MS. name of Mesoplodon 

 Floiveri, is for the first time described ; and another rostrum in the 

 Museum of Practical Geology, characterized by being very short 

 and with a deep boat-like anterior extremity, is named Mesoplodon 

 scaphoides. The peculiar species Ailurus anglicus, hitherto known 

 only by a piece of a lower jaw with a carnassial tooth, is now 

 further illustrated by a fine upper molar recently presented to the 

 Museum of Practical Geology. 



2. " On Burrows and Tracks of Invertebrate Animals in Palaeozoic 

 Rocks, and other Markings." By Sir J. William Dawson, LL.D., 

 F.R.S., r.G.S. 



This paper, which is illustrated by photographs and drawings, 

 indicates some new facts in connexion with the markings pro- 

 duced by the burrows and tracks of animals and by other causes. 

 BusicJmites and Cruziana are regarded, like Climacticlinites and 

 Protichnites, as representing probable burrows of Crustaceans and 

 Chaetopod worms. Scolithus canadensis is shown to be a cylindrical 

 burrow, with accumulations of earthy castings at its mouth. The 

 relation of these burrows to the forms known as Scotolithus, Astcro- 

 pJiycus, Monocraterion, and Astropolitlion is pointed out. 



Under the new generic name of SahelJarites the Author describes 

 certain tubes, composed of shelly and other fragments cemented by 

 organic matter, found in the Trenton Black-river Limestone. They 

 resemble the burrows or tubes formerly described by the Author 

 from the Hastings and Quebec Groups, and appear to be the tubes 

 of worms allied to the recent Sabellarice : but tliey are liable to be 

 mistaken for Algae of the genera Palcvophijeus and Buthotrephis. 



Some large cylindrical bodies from the Potsdam Sandstone are 

 described as having been supposed to be trunks of trees ; but the 

 Author regards them as probably concretions formed around slender 



