570 Reviews—Geology of North Cleveland, 
Rock are described, together with Glacial and Post-glacial deposits ; 
and there are notes on the Cleveland dyke, an augite-andesite, 
whose intrusion took place probably in Tertiary times. 
The Oolitic hills attain an elevation of 1078 feet on Guisborough 
Moor, while on the coast Boulby or Rockcliff, formed mainly of 
Lias, is nearly 700 feet high. 
The lower beds of the Lias have been proved in borings, but are 
only exposed at the surface in the “scars” seen at low-tide off 
Redcar. These beds were, however, described in such detail by 
Prof. Tate, that our knowledge of the paleontology is very full. 
The higher beds of the Lower Lias, with Ammonites Jamesoni, A. 
capricornus, etc., are briefly described, more detailed descriptions of 
the strata having been given in the Survey Memoir on the country 
between Whitby and Scarborough. 
From an economic point of view the most important portion of 
this Memoir is that dealing with the Ironstone Series of the Middle 
Lias, full details of which are given by Mr. Barrow. In the Upper 
Lias the Alum industry is now practically extinct, while the intro- 
duction of Spanish Jet has almost entirely stopped the local Jet- 
mining. The Ammonites furnish material. of much interest. Mr. 
Barrow observes that a perfect series can be found to show the 
gradual transition of Am. communis to the extreme types of A. 
crassus and A. Holandrei: facts which will not be disputed by 
those familiar with the variable forms obtained in the South of 
England. The doubtful identification of A. elegans, Young and Bird, 
with A. concavus, Sby., is at any rate interesting, while the occur- 
rence of A. radians (?), Rein., in the Alum Shale, is also noteworthy. 
The variable “‘ Dogger,” the base of the Inferior Oolite, occurs on 
top of the Alum Shale, and is ferruginous and pebbly—-the ‘pebbles,’ 
it is considered, being waterworn nodules from the Lias. Among 
other fossils Rhynchonella cynocephala, R. tetrahedra, and Terebratula 
punctata are recorded from the Dogger in Whitecliff Beck. 
The Hstuarine Series, grouped with the Inferior Oolite, includes 
representatives of the Eller Beck Bed and the Grey Limestone 
Series. ‘The Cornbrash is poorly represented, while the Kellaways 
Rock is well shown, and yields, among other fossils, Avicula braam- 
burtensis, a form characteristic of the marine bands in the Hstuarine 
Series below. 
The Drift obliterates all but the most strongly marked geological 
features of the country. It becomes very thin at heights of 600 feet 
' above sea-level, and disappears altogether above 850 feet. Mr. 
Barrow concludes, that the ice must have ground over the rocks with 
no slight force is proved by the fact that at Eston Hill a strip of the 
Main Seam (Middle Lias Ironstone), some 150 yards long, 50 
broad, and 11 feet thick, has been bodily lifted up the face of the 
hill to a point about 150 feet above its natural outcrop. It is also 
interesting to learn that the Drift deposits have blocked the old Pre- 
glacial valleys and forced the streams to form new channels, which 
they have cut out through deep gorges in the solid rock, in pre- 
ference to re-excavating their old course through the Boulder-clay. 
