part 1] 



AECHIMTLACEIS PEINGLEI. 



27 



It is evident that the relationship between these three species is 

 very close, 3^et the British specimen is clearly distinct. I have 

 much pleasm'c in giving Mr. Pringle's name to the species discovered 

 by him. 



Observations. — The occm-renceof a fossil Blattoidin Measures 

 formerl}^ regarded as Permian, and now classed as Upper Coal 

 Measures, is worthy of comment, especially as the fossil is more 

 closely related to Blattoids found in the Ccal Measures of Lievin, 

 Northern France, than to an}^ British species. The Coal Measures 

 of Lievin are generally accepted as being at the summit of the 

 Westphalian Series. Dr. Pruvost wa-ites that he has previously 



Fig. 



-Archimylacris lerichei jPruvost. x ^^ 



[For explanation of lettering-, see %. 2, p. 25.] 



drawm attention to the fact that the fauna at the top of the Coal 

 Measures in Grreat Britain (Keele Group, JSTewcastle-under-Lyme 

 Group, Etruria Group) does not differ (except in the presence of 

 AntJiracomya calcifera, peculiar to England) from the fauna at 

 the top of the Westphalian in Northern France. The occurrence 

 of an ArcTiimylacris in the Keele Group confirms him in this 

 opinion. 



The Keele Group in which the insect-wing was found was 

 formerly regarded as Permian, and is so marked upon the older 

 geological maps ; but the researches of the Survey Officers, as also 

 the palieobotanical work of the late Dr. Newell Arber, and more 

 especiall}'^ that of Dr. Kidston, have conclusively proved their Coal- 

 Measure character. These workers regard the Keele Group as 

 part of a true Upper Coal-Measure Series, widely spread over 



