1850.] BRODIE ON THE INFERIOR OOLITE. 245 



The most predominating genera are. Area, Avicula, Gervillia, Lima, 

 Ostrea, Pecten, and a new smooth species of Patella, common also 

 to the great oolite. The almost entire absence of the Cephalopoda 

 is remarkable, a small Ammonite and an imperfect Belemnite being 

 all at present known from this part of the inferior oolite ; and it is a 

 curious coincidence, that Mr. Lycett remarks the extreme rarity of 

 that class in the shelly beds of the great oolite. Besides Testacea, 

 there are many fragments of Pentacrinites, joints of Asterias, one spe- 

 cies of Comatula or Eugeniacrinus, a few small claws of Crustacea, 

 and teeth of Sharks, which are very scarce ; but no traces of the drift- 

 wood or rolled pebbles, so frequent at Minchinhampton. There are 

 also a variety of small corals, more or less abraded. Mr. Gomonde's 

 cabinet and my own contain upwards of one hundred and sixty spe- 

 cies of shells from the shelly freestone alone, many of which are pe- 

 culiar to the inferior oolite, and range indiscriminately through all 

 the beds ; some being confined to the shelly freestone, and a still 

 larger number identical with species which prevail in the great oolite. 

 In a series forwarded to Mr. Lycett, he identified ^^2/- ^z^o out of 

 one hundred and fifty -two species, previously recognised only in the 

 superior formation, and he was surprised to observe the proportion 

 so considerable. Mr. Morris had before noticed sixteen out of twenty- 

 six species in a choice collection first obtained by Mr. Gomonde from 

 Leckhampton Hill. My late lamented friend Mr. Pearce was so 

 struck with the lithological and zoological resemblance of these sub- 

 ordinate divisions of the freestone to the great oolite, that at first he 

 could scarcely believe the specimens in question were really obtained 

 from the inferior oolite. These facts certainly form an interestmg 

 and novel feature in the history of this deposit, and from them we 

 may infer that the shelly freestone, though of older date than cer- 

 tain beds in the great oolite at Minchinhampton, which it so closely 

 resembles, was deposited under very similar conditions, and the sea, 

 to which it owed its origin, still inhabited by many species of mol- 

 lusks, which previously flourished at a much earlier period*. It 

 would seem probable that this stratum was accumulated in a shallow 

 sea, at no very great distance from the shore, where strong currents 

 prevailed f, which accounts for the imperfect and abraded state of the 

 majority of the fossils. This statement is in a measure confirmed 

 by some remarks with which Professor Forbes has been kind enough 

 to favour me. He states, that "the assemblage of testacea, and the 

 conditions under which it occurred, seemed to him to indicate a 

 depth of somewhere about fifteen fathoms, in a sea vexed by cur- 

 rents. With respect to the valves of the shells being disunited, this 

 may happen at any distance from land, for in dredging forty or more 

 miles from the coast in the British seas, provided the bottom is con- 



* It should be remarked, that the fossils in the great oolite at Minchinhampton 

 are usually much larger, as well as more varied and abundant. Ample details are 

 given, and a copious catalogue of species, in Mr. Lycett's valuable paper in the 

 Quart. Journ. Geol. Soc. vol. iv. p, 181. 



t This agrees exactly with Mr. Lycett's opinion respecting the origin of the 

 shelly beds of the great oolite. 



