President's Address. 53 



these beds are largely develoj^ed, we find Schizodi in grega- 

 rious masses, forming complete beds.* 



Phillips' Family Solemyidce appears to have extended as 

 far back as the Carboniferous period, if we may judge from a 

 shell having all the apj)earance of the genus Soleniya 

 (Lamarck). This was first 2:>ointed out by the late Professor 

 Phillips, who described the only species, S. primcevcc.f The 

 resemblance of the internal details of the Carboniferous 

 fossil to those of the recent shell was afterwards shown by 

 Professor W. King.J A shell, referred to the genus San- 

 guinolitcs {S. radiatus, M'Coy §), probably forms a second 

 species. 



We now come to a very important group of Bivalves, com- 

 prised in the genus Anthracosia, and exclusively confined to 

 the true Coal Measures, unless a doubtful shell described by 

 Captain T. Brown from the AVardie shales, at Woodhall, 

 belongs to it. II Anthracosia has usually been placed in the 

 Family Unionidee, but the late Mr Salter, who extensively 

 studied this group of shells, has thrown doubts on the pro- 

 priety of such a reference. Mr Salter believed Anthracosia 

 to be a burrow er, after the habit of My a. He says, '' among 

 beds where these fossils were the only bivalves, I have seen 

 bivalve-burrows answering to them in size." IT These are met 

 with at Craig Hartle, in Fife.** But no distinct evidence has 

 yet been procured, so far as I know, of such a habit in this 

 genus. The evidence we at present possess appears to oscil- 

 late the genus between the Unionidse and the Myadae. I 

 do not at present see any reason for placing it with Saxicava, 

 as has been done by Dr Stoliczka."t"|" Anthracosia was in all 

 probability not a purely freshwater genus, but of brackish 

 water habit, for according to the researches of Salter, supple- 



* Rev. J. Brown, Trans. Roy. Soc, Edinb., xxii., 1861, p. 393 



+ Geol. Yorksliire, 1836, ii., p. 209. 



X Mon, Permian Foss., pp. 177 and 246. 



§ Synopsis, 1844, t. 13, f. 14. 



Ii Foss. Conchol. Gt. Brit., 1849, p. 178, t. 73, f. 8 ; Rliind, Age of the 

 Earth, 1836, ^\. 2, f. a; Etheridge, Quart. Jour. Geol. Soc., 1878, xxiv., 

 p. 16. 



% Iron Ores, p. 226. '^^ Etheridge, Expl. 23, p. 104. 



ti* Mem. Geol. Survey, India, iii., p. 81. 



