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VINE : PALEONTOLOGY OF THE WENLOCK SHALES. 
No. 6. Shales over Wenlock limestone, and these beds are repre- 
sented by Nos. 24 and 46. 
Speaking now generally of the shales which lie below the Wen- 
lock limestone it is estimated that they attain a thickness of from 
2000 to 2200 feet below the Shropshire escarpment. Immediately 
below the Wenlock limestone there are a series of beds which are 
conveniently called ''the Tickwood Beds," and these are roughly 
supposed to include a thickness of from 300 to 500 feet of strata. 
My Tickwood material is derived from three localities. 
No. 41 are washings from the shale under Wenlock limestone, at the 
foot of Benthal Edge and opposite Tickwood. 
„ 42 is from the road-side at Tickwood, between Buildwas and 
Wenlock. 
„ 25 is also from strata similarly described. 
It is very certain that these shales are differently derived although 
they are apparently belonging to one horizon.. In the No. 25 wash- 
ing, both coarse and fine, the organisms are far more perfect than in 
the washings from Nos. 41 and 42. Entomostraca are very abundant 
both in species and in individuals; the corals are more minute, and 
the Polyzoa and Annelida, though occasionally fragmentary, are better 
preserved than in any of the other beds. In the Nos. 41 and 42 
washings the fossils are larger and more tossed about, not altogether 
water-worn, than in No. 25, but the No. 42 washing is the best for 
the larger corals and also for the larger fragments of Trilobita. 
My own finer clay, from which I have picked out my best Ento- 
mostraca, was obtained by the re-washing of material derived from 
the No. 25 bed ; but as Mr. John Young, of Glasgow, requested Mr. 
Maw to send him some of the virgin material for washing and picking, 
I have no doubt that his No. 25x may have been obtained from a 
similar locality or horizon.''' I have not incorporated Mr. Smith's 
researches with my own, but have given to his pickings an indepen- 
dent page, especially so as all his organisms, excepting the Entomos- 
*The following- is Mr. Maw's description to Mr. Young, April 28th, 1881, 
" Tickwood beds, Wenlock series. Shale from east end of Benthal Edge, opposite 
Iron Bridge, Shropshire." 
