244 ON THE EXTINCT MAMMALIA OF 



agreeing with the corresponding tooth of the species just named in size and constitu- 

 tion, and differing only in a greater degree of development than usual of the abut- 

 ments of the inner lobes, by which the valleys of the crown are in a proportionate 

 degree obstructed. 



Mastodon ? — In 1858 Dr. Richard Harlan, a son of the late American 



naturalist of that name, desired me to inspect a collection of natural history speci- 

 mens which liad belonged to his father, and which had been stowed awaj' in the 

 garret of a warehouse upwards of twenty years previously, where they had remained 

 untouched until the time the subject was mentioned to me. In the collection I 

 observed the plaster cast of a Mastodon tooth, which struck me from its resemblance 

 to a certain tooth of somewhat enigmatic character preserved in the Museum of this 

 Academy. My suspicion that it was a cast of the latter tooth appeared to be con- 

 firmed on turning over the cast, and finding within the hollow of the crown an 

 attached label, inscribed "Mastodon longirostris, Miocene, Maryland." Notwithstand- 

 ing an extraordinary likeness, subsequent examination and comparison proved that 

 the cast was derived from a different specimen. 



The original of the cast is lost, and appears to be that referred to in a paragraph, 

 page 38 of vol. iv, 1843 to 1845, of the Proceedings of the Geological Society of 

 London, which reads as follows: "In the Museum of Baltimore Mr. Lyell was shown 

 the grinder of a Mastodon, distinct from M. giganteum, and which had been recog- 

 nized and labelled by Mr. Charlesworth as M. longirostris, Kaup. It was found at the 

 depth of fifteen feet from the surface in a bed of marl near Greensburgh, Caroline Co., 

 Maryland, and is considered by Mr. Lyell as a miocene fossil." 



The original is also referred to by Dr. Warren, in his work on the Mastodon 

 giganteus of North America, under the article headed " The Baltimore Tooth," page 

 78. \ He observes : " Dr. Ducatel, of Baltimore, being engaged as geological surveyor 

 of the State of Maryland anterior to 1840, noticed a spot in Caroline county, near the 

 banks of a small river, where he thought some valuable fossils might be discovered. 

 From this place a Mastodon tooth was obtained, which remained in the possession of 

 Dr. Ducatel for some time without attracting much attention. Mr. Charlesworth, 

 when travelling in this country, pronounced it to be a grinder of the Mastodon longi- 

 rostris. Some time after, being seen by Sir Charles Lyell, he gave for opinion that it 

 was the tooth of a species distinct from the Mastodon giganteum. Dr. Hays and Dr. 

 Harlan were of the same opinion. The specimen belonged at the time to a collection 

 in the Academy at Baltimore, where it was permanently deposited." Dr. Warren 

 continues: "In the year 1843 a statement was made by Mr. Lyell on the miocene 

 deposits of the United States, in which he noticed this tooth. Having a curiosity to 

 see it, being at Baltimore in 1848, I applied for an opportunity of examining this 



