124 BRITISH FOSSIL ELEPHANTS. 



of spiculated particles of cancellated bone, and earthy material.^ There is a loss by dentri- 

 tion of the fore part of each molar, which holds 13 <t' in 9 X 3f . The enamel is tldck^ with 

 much cement and some crimping of the machaerides ; indeed, eight ridges are contained 

 in 4f inches, which show the great thickness of the plates as compared with the usual 

 crowns from the Arctic regions. 



The molars converge considerably, being 2*9 inches apart in front, 3f at their middle, 

 and 3f posteriorly. The ramus is 7 inches in thickness at the base of the coronoid. 

 The jaw has all the characters of that of the Mammoth already noticed.^ 



Another nearly entire mandible in the British Museum, dredged off Harwich, 

 presents some rather remarkable peculiarities. The two molars are in full wear, with a 

 loss of some ridges in front by detrition, without a trace of a third tooth in the cavity 

 posteriorly, as proved by inspection, although the round prominent heels are elevated, 

 and 2^ inches behind the anterior border of the coronoid.^ Each molar holds seven- 

 teen plates in 10^X3| inches, and is considerably arcuated and converges; the distance 

 between them in front is 3 inches, at the middle 3^, and behind 1\ inches. The 

 maximum length of the jaw from the posterior border of the ascending ramus 20 inches. 

 Height in front of the molar 8^ inches. Maximum thickness of the ramus ^\ inches. 

 Maximum expanse of the jaw at the middle of the ascending ramus 20 inches. The 

 diasteme is perpendicular. 



The numerous molars of the Mammoth derived from peat at Lexden, near Colchester, 

 Essex/ several of which have been already noticed, point to the fact that the thickness 

 or tJdnness of the enamel cannot always be depended upon as characteristic of races or 

 local varieties, although, as has been shown, it is peculiarly thin in Arctic and the so- 

 called Ohio and North-American molars, as well as in many teeth from British strata. 



The mandible (No. 95, Eisher Collection) in the Woodwardian Museum contains 

 two ultimate molars from Lexden. The teeth are very much detrited, indeed, they 

 are nearly worn out, seeing that the heel is only an inch behind the anterior border of 

 the coronoid. The rami are lost just behind the teeth, but a fragment of the plug remains 

 in the space which a succeeding molar would have occupied. Only eleven to twelve 



^ In the mandibles (2674 and 2664) of Asiatic Elephants in the Museum of the Royal College of 

 Surgeons of England, the heels of the first true molars, which are in full wear, are almost in line with 

 the anterior border of the coronoid, whilst the second has four collines appearing above the gum, and six 

 Tisible, but none are nearly on a level with the grinding surface of the tooth in use. 



2 The portion of a mandible with two molars holding thirteen worn plates is well shown in the 

 * Fauna Antiqua Sivalensis,' pi. xiii a. The teeth are of such gigantic dimensions that I cannot help 

 assigning their age to be exactly as represented by the Siberian jaw just noticed, i. e. an ultimate molar 

 more than half detrited. Falconer had not evidently made up his mind on that subject, ' Pal. Mem.,' 

 vol. i, p. 439. 



^ The mandible 2675 (Asiatic Elephant), Royal College of Surgeons Museum, has the second true 

 molar with twelve to thirteen ridges invaded, and the heel two inches behind the anterior border of the 

 diasteme. The vault of the third molar is broken through, and the tips of the collines are just visible. 



* Seep. 110. 



