Dr. C. I. Forsyth Major — Vliohyrax from Samos. 547 



ci'ystals which occur in some of these are slightly or extensively 

 serpentinized, and whether also the recently discovered nepheline- 

 -syenites of Ontario, which are old enough to be crushed and foliated, 

 contain fresh or altered nepheline. 



" Just what would be the effect of prolonged submergence in sea- 

 water on a mass of olivine rock," Professor Merrill is not prepared 

 "to say. Neither am I. But I see no flagrant theoretical objection 

 to serpentinization under such conditions. On the contrary, it is 

 theoretically to be expected that sea-water, acting under high 

 pressure, would permeate rocks to greater distances,^ and, being 

 charged with carbonic acid as well as salts of lime, magnesia, and 

 the alkalies, would form a more destructive reagent than rain-water 

 when in contact with unstable silicates. 



It is easy to foresee many difiScnlties which must be met should 

 the submarine theory attain a maturity that warrants deductive tests. 

 At present it has not reached that stage ; for although the evidences, 

 both positive and negative, from India indicate that a submarine 

 existence has formed part of the history of every mass of serpentine, 

 it will require the testimony of other areas to show that such 

 submarine conditions are essential for serpentinization on an extensive 

 scale. 



In conclusion, it should be stated that Professor Merrill's paper has 

 <lrawn me into this discussion earlier than was anticipated. Although 

 the question has been under consideration for some years, the facts, 

 -so far, at my disposal warrant no further deductions than those 

 tentatively offered for discussion at the meeting of the British 

 Association. Keeping in view the fact that a mineral may be 

 produced by more than one of the ways into which we classify the 

 processes going on in Nature, recent observations indicate a fairly 

 definite classification of the usual conditions under which secondary 

 hydrous minerals are produced. Until these are established with 

 more certainty, however, the formulation and definition of precise 

 general terras might pi'ofitably be replaced by the accumulation of 

 details concerning the paragenesis of each mineral. 



IV. — The Hyracoid Pliohybax gbjscvs (Gaudry) from the 



Upper Miocene of Samos and Pikermi. 



By C. I. Forsyth Major, M.D., F.Z.S. 



(PLATE XXIV.) 



AMONGST the hosts of Antelopes, Rhinoceroses, Hipparions, etc., 

 which form the bulk of the Pikermi fauna described in Gaudry's 

 ■classical " Animaux Fossiles et Geologic de I'Attique," the mandible 

 of Leptodon grcecus,'^ with lower molars recalling the Pal^otheres 

 and Paloplotheres, seemed to stand out, as it were, as an anachronism. 

 It has always appeared to me, as it may also have to others, that 

 the occurrence of such a type in the above company (with which 



^ Cf. J. D. Dana, Amer. Joiirn. Sci., vol. xlix (1845), pp. 57 and 58. 

 2 A. Gaudry : "Animaux Fossiles et Geologie de I'Attiqu^," 1862, p. 215, 

 ;pl. xxxiv, figs. 1,2. 



