220 Geological Society. 



jects may be made to delineate themselves without the aid of the 

 Artist's Pencil." By H. F. Talbot, Esq., F.R.S. 



This paper is given, entire, in the present Number, p. 196. 



February 7. — A paper was read, entitled, " Notice of a Shock of 

 an Earthquake felt in the Island of St. Mary's, one of the Scilly 

 Islands, on the 21st of January, 1839," in a letter addressed to the 

 Secretary. By the Rev. George Wordley. 



The tremulous motion of the ground is described as being very 

 slight, and felt chiefly in the south parts of the island. It was ac- 

 companied by a peculiarly harsh and grating soimd, which was only 

 of momentary duration, and no particular agitation of the sea was 

 obsen'ed. 



A paper was in part read, entitled, " Observations on the Parallel 

 Roads of Glen Roy, and of other parts of Lochabar, with an attempt 

 to prove that they are of Marine Origin." By Charles Darwin, Esq., 

 M.A., F.R.S., Sec. Geol. Soc. 



GEOLOGICAL SOCIETY. 

 [Continued from p. 151.] 



Dec. 9, 1838. — A paper on the " Phascolotherium," being the 

 second part of the " Description of the Remains of Marsupial 

 Mammalia from the Stonesfield Slate," by Richard Owen, Esq., 

 F.G.S., was read. 



Mr. Owen first gave a brief summaiy of the characters of the 

 " Thylacotherium," described in the first part of the memoir*, and 

 which he conceives fully prove the mammiferous nature of that 

 fossil. He stated, that the remains of the split condyles in the spe- 

 cimen demonstrate their original convex form, which is diametrically 

 opposite to that which characterizes the same part in all reptiles 

 and all ovipara ; — that the size, figure and position of the coronoid 

 process are such as were never yet witnessed in any except a 

 zoophagous mammal endowed with a temporal muscle sufficiently 

 developed to demand so extensive an attachment for working 

 a powerful carnivorous jaw ; — that the teeth, composed of dense 

 ivory with crovras covered with a thick coat of enamel, are everywhere 

 distinct from the substance of the jaw, but have two fangs deeply im- 

 bedded in it ; — that these teeth, which belong to the molar series, 

 are of two kinds ; the hinder being bristled with five cusps, four of 

 which are placed in pairs transversely across the crown of the teeth, 

 and the anterior or false molars, having a different form, and only 

 two or three cusps — characters never yet found united in the teeth 

 of any other than a zoophagous mammiferous quadruped ; — that the 

 general form of the jaw corresponds with the preceding more essen- 

 tial indications of its mammiferous nature. Fully impressed with 

 the value of these characters, as determining the class to which the 

 fossils belonged, Mr. Owen stated, that he had sought in the next 

 place for secondary characters which might reveal the group of 



• An abstract of the first part of Prof. Owen's memoir was given in 

 our last Number, pres. vol. p. 141. Edit. 



