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attention. The features of the Middle Lias, in the county he 

 describes, are so like those of the Gloucestershire Lias, that in 

 the vignette of the village of Somerby, Rutland, situated in one 

 of the deep sinuous valleys of the great escarpment formed by 

 the Marlstone Rock, if the word Churchdown had been written 

 under it, we could not have distinguished it from the saddleback 

 leading from Churchdown Hill to Tinkers' Hill. In Rutland 

 the Marlstone attenuates rapidly from 18 ft. 6 inches to 1 foot, 

 (see p. 65) "It loses its calcareous character and becomes 

 sandy," and " when the junction of the Upper Lias clay and 

 the Marlstone rock-bed is seen, the latter presents the appear- 

 ance of having suffered erosion before the deposition of the 

 former," and " taking into account all the characters presented 

 by the Marlstone rock-bed, and remembering the evidence of 

 shallow water conditions the beds {i.e. the Spinatus heds) 

 immediately lying upon it exhibit, it seems probable, that an 

 interval occurred between the deposition of the Marlstone and 

 Upper Lias ; but when we remember the fact of the passage of 

 certain species from the one to the other, especially of the Planulate 

 Ammonites, it is clear that this interval was not one of long 

 duration." This might have been written of the Grloucestershire 

 Spinatus beds, so that, externally and palseontologicaly, there 

 is unity as to operation and results, between the Middle Lias of 

 the Midland counties and our own. Mr. Jtjdd finds in the Spinatus 

 Zone of Rutland that the Am. Spinosus is rare, but Belemnites 

 paxillosus and elongatus are abundant and often of large size. 

 Though loth to multiply instances, we pause to mention the 

 exceedingly good Jurassic series that we are acquainted with, 

 through a communication of the Rev. J. E. Cross in 1875, 

 " The geology of N. W. Lincolnshire" (Quarterly Journal, Geol. 

 Soc. XXI, p. 115). To this instructive succession ranging from 

 the Keuper up to the Great Oolite, inclusively, attention has 

 been drawn by the discovery of an extensive deposit of valuable 

 iron-ore that is being worked from the middle of the Lower 

 Lias. The district has also its special value for the geologist, 

 inasmuch as it supplies a connecting link in the chain of the 

 Jurassic strata from Whitby to Charmouth. We natiu-ally turn 



