148 MESSES. A. J. JUEES-BEOWNE AND W. HILL : [May 1 896, 



censis is certainly different from the typical T. sella, so that it is 

 only the smaller varieties and the distorted forms which resemble 

 one another,. 



Subsequently ( 4 Supplement,' 1874, pp. 35, 36), and after 

 correspondence with Mr. Meyer, Davidson was led to alter his 

 opinion so far as to admit that the forms previously attributed to 

 T. tornacensis were really only varieties of T. sella. 



We agree with Mr. Meyer in regarding T. tornacensis as essen- 

 tially a Cenomanian species, and we are able to state that it occurs 

 in the typical Cenomanian of Le Mans, where it seems to have been 

 confused with T. biplicata. M. Bizet has sent ns three specimens 

 under the latter name which in the opinion of Mr. Me er and our- 

 selves are typical T. tornacensis, differing from biplicata by the very 

 characters pointed out by d'Archiac. 



In Devon a few specimens have been found by Mr. Meyer in the 

 beds described by him as 11 and 12 at Beer Head. 



Whether the real T. biplicata occurs near Le Mans as well as 

 T. tornacensis we have no means of knowing, but it does not seem to 

 occur in Devon and it does not occur in the Tourtia of Tournay ; it 

 is common in the Chloritic Marl of the Isle of Wight, and occurs in 

 that of Havre, as well as at Orbiquet (Calvados) and Yimoutiers 

 (Orne). 



Teeebeatela aeenosa, d'Arch., op. cit. p. 324, pi. xxi. figs. 1-3. 



This is another Tourtia form recognized by Mr. Meyer in the 

 Devon Cenomanian. It is a small globose species, the surface of 

 which bears scattered granules or small tubercules with depressed 

 summits, so that they resemble minute craters. It might easily be 

 passed over as a globose form of Megerlia lima. 



Teeebeatela Veeneeilii, d'Arch., op. cit. p. 326, pi. xx. fig. 4. 



This shell is not likely to be mistaken for any other species, as it 

 bears a very remarkable ornamentation on both valves. They 

 display a series of short, strong ridges, arranged in concentric rows 

 and separated by oval indentations or hollows, so that the shell seems 

 covered by a raised crochet-work pattern. The hollows are deepest 

 at the top, and those of one row lie below the ridges of the row 

 above. In the adult shell these ornamental ridges die away towards 

 the edge of the shell. 



Mr. Me\er has found this form in the same bed at Beer Head 

 as that which contains T. tornacensis and T. arenosa. 



Teeebeatela capillata, d'Arch., and T. squamosa, Mantell. 



We think that there is a much closer connexion between these two 

 species than has hitherto been supposed. In discussing the rela- 

 tions of T. capillata Davidson only distinguishes it from T. depressa, 

 to which d'Orbigny had imagined that it had some resemblance ; 

 and in describing T, squamosa he does not mention T. capillata. Yet 



