﻿252 INFERIOR OOLITE AMMONITES. 



The woodcut, fig. 2 in the text (p. 187), is a copy of Reinecke's original figures 

 given for comparison with the examples depicted in the Plates. 



Dumortieria kadians, var. exigua, S. BucJcman. Plate XLIII, figs. 11 — 13; Plate 



XLIV, figs. 1—3. 



1830. Ammonites striatulus, Zieten (non Sowerby). Verstein. Wiirtt., pi. x\v, 



fig. 6. 

 1885. — cf. radians, Quenstedt. Amm. Scbwabischen Jura, pi. liv, 



fig. 19. 



Zieten's figure represents this form exactly, except that it is a little thicker in 

 the aperture than my examples. These fossils differ from Bum. radians in 

 combining a more compressed form with a rather large umbilicus and very slight 

 inclusion of the whorls. The size of the umbilicus separates them particularly 

 from the specimen depicted, PI. XLII, figs. 6, 7, which resembles them in being 

 much compressed. 



The larger umbilicus and the coarser radii separate this form from 

 Bum.. Moorei. 



Dr. Haug ttlls me that these specimens have great resemblance to his Bum. 

 rhodanica (see p. 250), but are a trifle thinner. This, I think, is just the point 

 which is noticeable; but they also have finer ribs. Dr. Haug recognises figs. 6 — 

 12, PI. XLII, as rhodanica; but the specimens there depicted I have admitted as 

 radians, and this variety differs from them in the manner just noticed. 



Haug (" Polymorphidas," p. 139) cited the reference to Zieten as a synonym of 

 his Bum. suevica, only he expresses some doubt in the matter. Bum. suevica is, 

 accordiug to Haug, a keelless form, and is very much thicker, judging from 

 Quenstedt's figs. 9, 10, pi. lii (' Schwab. Amm.'), upon which Haug has founded his 

 species ; and it is therefore essentially different from the present form. 



Bumortieria radians, var. exigua, is a scarce fossil. I have obtained it at 

 Penn Wood, and Buckholt Wood, near Stroud, and at Sodbury, Gloucestershire. 

 PI. XLIII, figs. 11, 12, represent a specimen from Penn Wood; and fig. 13 is a 

 suture-line from another specimen. 1 PI. XLIV, figs. 1, 2, show a larger example 

 from the same place ; while fig. 3 is the suture-line of this specimen. 



1 The specimen from which this suture-line was traced has been mislaid, so that I do not know 

 the reason for the discrepancy between this and fig. 3, PI. XLIV. 



