410 



FOSSILS FKOM PEKIM ISLAND. 



vertical height of the oiiter surface of the jaw. Part of the outer layers 

 of the bone has recently been denuded from the external surface ; the 

 mentary foramen is of inconsiderable size. The specimen consists of 

 two fragments, the larger of which bears the label No. 12, to which a 

 smaller fragment (No. 47) was fortunately added, yielding the first 

 indication of the downward deflection of the symphysial portion. The 

 mentary foramen is of no great size ; the diastemal edge is raised, and 

 very sharp, and follows an outward direction, where the anterior part of 

 the ramus commences to be bent inwards. 



Unfortunately aU evidence derivable from the crowns of the teeth 

 as regards the degree of composition and complexity is entirely wanting. 

 The principal dimensions are as foUow : — 



Inches 



1. Extreme length of the fragment taken at the inferior margin (as 



a chord to the arc) ......... 7"75 



2. Versed sine of the concave arc of the lower jaw, when rested upon 



the ends of the fragment ........ 



3. Vertical height of ditto, at anterior termination of the diasteme . 



4. Vertical height of the jaw, in a line with the anterior molar 

 6. Greatest thickness of the jaw behind ...... 



6. Ditto in a line with the mentary foramen ..... 



7. Length of the remains of the diasteme ..... 



8. Vertical height of the supx^osed alveohis, of the incisor 



0-8 

 5-0 

 61 

 2-8 

 2-2 

 2-2 

 3-2 

 1-5 



The supposed alveolus of the incisor is filled up with conglomerate 

 matrix, and its definition imperfectly shown. 



This is a very important specimen, and thin sections, both of the 

 ivory of the teeth, and of the compact bone, ought to be taken for 

 microscopical investigation. As an approximative opinion, I am inclined 

 to consider it as of a Dinotherian form, and it may be, of a yormg Dino- 

 thermm Indicum ; but the contour of the lower jaw in that species is so 

 imperfectly known that nothing more positive can be asserted in regard 

 to it.i 



London, 31 Sackville Steeet: 

 March 1858. 



11. — MS. Note by Dr. Falcoker. — Microscopic Examination of Mr. 

 Tait's supposed Vertebra of Dinotherium from Perim Island. 



Vertical Section. — ^Viewed with ^ inch object glass, the length of one 

 of the cells of Purkinje is -^^ inch and the width -^^ o . Their form 

 is long and ragged, and attenuated at either end, like an insect with in- 

 numerable legs. The measurements of another cell were -f^ in. and 45^. 

 The calcigerous tubes are yy' 



of an inch apart. Seen in transverse 



' Among other specimens from Perim 

 Island in Mr. Duckworth's collection. 

 Dr. Falconer identified remains of 

 Mastodon, Hipp(fpotamus, Beer, Antelope, 

 Crocodile, and Tortoise. In another col- 



lection from Perim Island, forwarded by 

 Dr. Buist, of Bombay, in 1860, Dr. Fal- 

 coner identified remains of Mastodon 

 Perimensis, Bhinoceros, Bramatherium, 

 &c.— [Ed.] 



