JOURNAL OF MICROSCOPICAL SCIENCE. 



DESCRIPTION OF PLATE XVI., 



Illustrating Rev. J. B. P. Dennis's paper on a Fossil Bone, 

 supposed to be Mammalian. 



Fig. 



1. — Eepresents the fossil rib from Lyme Regis. Natural size. 

 2. — Tangential section. Magnified 100 diameters. 



2 a. — Portion of tlie above, at a, showing the character of the lacunaj and 

 canaliculi, in connexion with an haversian canal. Magnified 

 400 diameters, for comparison with fig. 8. 

 2 b. — Portion of fig. 2, at b. Magnified 400 diameters. 

 3. — Longitudinal section of the Lyme Eegis bone, magnified 100 dia- 

 meters, to show the general arrangement of the lacunse. 

 4. — Single lacuna of fossil. Magnified 400 diameters. 



Figures A to G represent typical lacunae under the same 

 degree of enlargement. 

 A. Human. B. Tiger. Mammalian. C. Boa Constrictor. 

 D. Crocodile. E. Fossil Saurian from Stonesfield. 

 F. Turtle. Reptilian. G. Conger Eel. Fish 



5. — Fossil Saurian from Stonesfield. Magnified 100 diameters. 



6. — Lyme Regis fossil, vertical. Magnified 400 diameters. 



7. — Tertiary Mammal. Magnified 400 diameters. 



8. — Walnis, transverse ; lacunar in the neighbourhood of an haversian 



canal. Magnified 200 diameters. 

 9. — Fossil Cetacean. Magnified 400 diameters. 

 10. — Fossil Elephant. Magnified 400 diameters. 

 11. — Ant-eater. Magnified 400 diameters. 

 12.— Sloth. Magnified 400 diameters. 

 13. — Dolphin. Magnified 400 diameters. 

 14. — Dugong. Magnified 400 diameters. 



The resemblance of this latter to the fossil in question is very 

 striking. 

 15, 16, 17, 18. — Ant-eater, Sloth, Dolphin, and Dugong, magnified 100 

 diameters, to show the general arrangement of the lacunae and 

 canaliculi. 

 19. — Crocodile, transverse. Magnified 200 diameters. 

 20. — Toad, tibia, vertical. Magnified 200 diameters. 

 21. — Sturgeon fin, vertical. Magnified 200 diameters. 

 22. — Fossil fish {Pycnodontus), from Stonesfield. 



