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SUPPLEMENT TO THE BRITISH 



80. Var. submaxillata, Morris. Dav., Ool. Mon., p. 51, PI. IX, figs. 10—12. 



In his paper on the Cotteswold Hills, Mr. Lycett states that T. submaxillata is a 

 shell whose numerous phases of form exemplify the difficulty of separating it, even as a 

 variety, from the Cornbrash T. maxillata. In the Cotteswold Hills T. submaxillata is 

 found in the Oolitic Marl series (which is the third or highest division of the Eimbria- 

 stage of the Inferior Oolite), associated with the following Brachiopoda : — T. fimbria, 

 Wald. curvifrons, T. galeiformis, T. plicata, T. simplex, Rh. subobsoleta, Rh. concinna, 

 and Rh. subtetrahedra. 



Mr. Jones, of Gloucester, is also of opinion that a merely cursory examination of a 

 series of so-called T. submaxillata from the Pisolite and Marl of the Inferior Oolite, as 

 compared with each other and the type from the Great Oolite, as illustrated in his 

 collection, will lead to the conclusion that they must certainly be regarded as one 

 species. 



I distinctly stated at p. 51 of my Monograph that the shell under description cannot 

 be separated specifically from T. maxillata, but that I have observed certain small 

 differences in the form found in the light yellow clay bed of the middle division 

 of the Inferior Oolite, to which it might be desirable to give a varietal designation. 

 Mr. E. Deslongchamps, in his ' Paleontologie francaise Brachiopodes jurassiques,' would 

 go much further and make of it a distinct species. Mr. Walker justly remarks that it is 

 easy with selected specimens to prove anything ; for out of several thousand one can find 

 •abnormal examples in any genus, and by placing these between a series arranged of 

 different species one can appear to have connected them together. He adds that he 

 regards a species as a centre round which individuals are thickly clustered, and that the 

 spaces between these centres may be either devoid of individuals, or may contain here 

 and there an abnormal form. 



81. Terebratula perovalis, Sow. Dav., Ool. Mon., p. 51, PI. X, figs. 1 — 6; Sup., 



PI. XVII, fig. 9. 



I have not much to add or alter with respect to this well-known species. Mr. E. 

 Deslongchamps in his 'Brachiopodes jurassiques, Paleontologie francaise' (p. 197) gives 

 a long list of synonyms and references to which the student is referred. Among other 

 things he states that it is difficult to know what is the first name that was given to the 

 species, — that in the ' Atlas of the Encyclopedic Methodique,' Bruguiere gives a good 

 figure of the species, vol. iii, pi. ccxxxix, fig. 5, but without a name, — and that in 



