110 Woodward and Etheridge — On Bithyrocaris. 



The front border appears to have been roundly produced on each 

 side with a shallow median indentation; the posterior border was 

 no doubt furnished with two lateral spines, having the usual mesial 

 indentation between them. 



The surface of the carapace is plain; the maxillary ridges are 

 not seen. 



Locality and Formation. — In greenish-grey shale of the Lower Old 

 Ked Sandstone, Carmichael Burn, S.E. of Lanark, associated with 

 Orthoceras dimidiatum, Sow., etc. Collected by Mr. A. Macconochie. 

 In the Collection of the Geological Survey of Scotland. 



Position of the beds from which the foregoing species were obtained. 



The preceding five^ Carboniferous species of Bithyrocaris were 

 all obtained from the shale overlying the Calderwood Cement Stone 

 of the East Kilbride district, Lanarkshire. 



The Calderwood Cement Stone is worked at Calderside and East 

 Kilbride, where it attains an average thickness of about ten inches. 

 According to Mr. James Geikie, District Surveyor of the Geological 

 Survey of Scotland, it is the equiA^alent of the calmy limestone over- 

 lying the First Kingshaw Limestone of the Lower Carboniferous 

 Limestone Group of the Carluke District. The Cement Stone near 

 East Kilbride is succeeded in a descending order by three limestones, 

 locally known as the No. III., II., and I. Calderwood Limestones, 

 with their intervening and accompanying shales, certain of which 

 have proved very fossiliferous, especially that between the two 

 lowest, or Nos. I. and II. Limestones of the section. From this 

 band of shale, at the foregoing and other localities of the district, 

 many of the rarer Carboniferous fossils, in addition to those of more 

 common occurrence, have been obtained both by the collector of the 

 Geological Survey, Mr. J. Bennie, and by local collectors, especially 

 Mr. A. Paton, of East Kilbride. Amongst these fossils may be 

 mentioned six species of Foraminifera, which were kindly deter- 

 mined for the Survey by Mr. H. B. Brady ; they are, Endothyra 

 ammonoides, Brady, MS. ; E. Bowmanni, Phil. ; E. globolus, Eichw. : 

 TrocJiammina incerta, D'Orb. ; Valvulina plicata, Brady, MS. ; and 

 Webbina acervalis, Brady, MS. ; both species of Prof. Duncan's genus 

 Palceocoryne, P. Scoticum, and P. radiatum ; amongst Annelida, 

 Spirorbis caperatus, McCoy, and Ortonia carbonaria, J. Young ; many 

 Bntomostraca and Polyzoa, including De Koninck's recently described 

 Archceopora nexilis. with many Brachiopoda, and other Mollusca. 



The sixth species here described, D. ? striata was obtained from the 

 Lower Old Eed Sandstone at Carmichael Burn, near the Manse, 

 about 4^ miles south-east of Lanark, in greenish-grey flaggy shale, 

 by Mr. A. Macconochie, Geological Survey Collector. (Vide Sheet 

 and Explanation, 23, Geological Survey, Scotland, 1873, pp. 14, 57, 

 and 100.) 



• Two of the species of Bithyrocaris were described in the First Part of this Paper, 

 See Geol. Mag. 1873, Vol. X. p. 482, PI. XVI. 



