514 E. B. Woodtvard—On the Mid/ord Sands. 



that the faunas of the Upper Lias and Sands are very distinct in 

 general facies, and that many Ammonites pass from the Sands into 

 the Inferior Oolite above. The Sands, moreover, he states, are often 

 inseparable from the Inferior Oolite into which they pass gradually 

 upwards ; while he mentions that at Compton, near Sherborne, the 

 tipper surface of the Upper Lias, composed of thin bands of clay and 

 stone, " was much eroded before the deposition of the Oolitic bed 

 above, a circumstance observable wherever the junction of the 

 Upper Lias with the Sands is exposed." 



This last statement, however, is at variance with that of other 

 observers, who regard the beds as passing one into the other ; and as 

 the fossil evidence tends to confirm the opinion, we are inclined to 

 regard the appearance of erosion as a local peculiarity. Unfortunately 

 the junction of the Sands with the Lias is very rarely seen in section, 

 although usually it is clearly marked by springs which are thrown 

 out by the Upper Lias Clay. 



Judging solely from Dr. Wright's list of fossils we find that 

 taking into consideration the Cephalopoda alone, the Sands are 

 more nearly related to the Upper Lias ; while arguing from the 

 Gasteropoda, Conchifera, and Brachiopoda, they are more closely 

 allied to the Inferior Oolite. 



Therefore the pal^ontological evidence cannot be looked upon as 

 decisive for referring the Sands more particularly either to the 

 Upper Lias or the Inferior Oolite, but that it agrees with the evi- 

 dence afforded by the rocks of a gradual change. 



This is indeed the opinion arrived at by Mr. Lycett ^ in the Cottes- 

 wold Hills. Here he has called the Sands the " Cynocephala stage," 

 from their being characterized by Bhynclionella cynocejjTiala, which 

 occurs in the " Ammonite bed " (=" Cephalopoda bed" of Dr. 

 Wright). He observes that it is a stage " possessing some features 

 both petrographic and zoological, which seem to claim for it a posi- 

 tion intermediate and connecting the Lias with the Inferior Oolite." 

 He considers that the group of fossils found in the "Ammonite bed" 

 differs very materially from the Upper Liassic fauna, and that even 

 the evidence afforded by the Ammonites is "transitive" in its 

 character. He also alludes to the division between the " Ammonite 

 bed" and the Oolite above, as being often very indistinct. 



Professor Phillips^ has pointed out the transitional character of 

 the Midford Sands as a very general fact in Yorkshire, Lincolnshire, 

 Gloucestershire, and Dorsetshire ; that they were " deposited on the 

 Upper Lias clay in such a manner as often to defy the geologist to 

 draw a hard line between them," and that " the Oolite above seems 

 to connect itself with equal affinity to shelly calcareous rock [the 

 Cephalopoda bed] at its base." And in regard to the organic re- 

 mains, he remarks that, " before the Liassic life has come to an end, 

 the Oolitic life has begun," 



It is important, however, to notice the statement of Mr. Moore in 



1 The Cotteswold Hills. Hand-Book introductory to their Geology and Palaeontology, 

 pp. 16-33. (London, 1857. 8vo.) 

 - Op. cif., p. 118. 



