2G2 DESCRIPTION OF FIVE NEW SPECIES 



ti-ack having the same relative position upon another part of the 

 specimen. The probaliility, therefore, is, that this is the track of 

 a quadruped. Indeed, ils appearance is like the track of a I'our- 

 footed animal. Yet it difl'ers from the Cheirotherium in having 

 only three toes besides ihe thumb. Still the shape of the toes 

 corresponds well to those of the Cheirolherium. 



If I am not mistaken, then, this is the first example in which I 

 have any certain evidence that any of the numerous tracks upon 

 the sandstone of the Connecticut valley were made by a quadru- 

 ped : though, as will be seen by reference to my Final Report, I 

 strongly suspected such might be the case in respect to several of 

 them. There is another interesting fact shown by the specimen 

 under consideration. Its surface has that pitted appearance which 

 was probably the result of rain drops. The tracks were evidently 

 made afterwards. We hence learn that the surface was above 

 the waters at the time both the impressions were produced. But 

 it must have been subsequendy submerged to bring over it another 

 layer of mud. 



There is a close approach, in the track I have now described, 

 to the Om\\ho\dic\mi\cs parvulus of my Report; except that the 

 latter has only three toes. But as I possess only a single speci- 

 men of O. parviilus, and that considerably w^orn, it w^ould not be 

 strange if both these species should prove to be identical. But 

 until a fourth toe shall be discovered on the O.parvvliis, we can 

 hardly make of it a Sauroidichnites. 



Dr. Deane has recently discovered a new locality of Ornithoi- 

 dichnites giganteu.s, in the northeast pail of Deerfield, at a small 

 quarry half a mile south of the bridge over Connecticut river. 

 He finds, also, fine examples of rain drops at Tm-ner's Falls. I 

 have discovered the same at the localities of footmarks in Mon- 

 tague and Northampton. I would state, also, that I have lately 

 noticed several cases of the impressions of rain drops on mud, 

 after a shower, exactly resembling tliose on stone, and produced 

 in the following manner. During the shower, fine mud was 

 carried into depressions of the surface, from which the water soon 

 escaped ; and near the close of the shower, a few large drops of 

 rain fell, as is often the case, and produced the pitted appearance 



