594 ME. LINSDALL KICHAEDSOIST ON" [Nov. I906, 



incurved, smooth exteriorly, of which the total length is 23 mm. ; this fragment 

 has been in part broken, and the length of the well-preserved portion does not 

 exceed 13 mm. The section is elliptical (the greatest dimension of this section, 

 in the middle, being 3 mm., and the least dimension 2 mm.). Upon the whole 

 it is a poor specimen, scarcely characteristic, of which the. interest is in pre- 

 senting so aberrant a form for a Dentalium! 



He adds in a postscript that the compressed form of the tube is 

 certainly not due to any mechanical action after fossilization : ' the 

 tube is intact in the part considered/ 



From M. Chenevrier's useful description, one would feel disposed 

 to think that D. compressum, d'Orb., is not a Dentalium at all, but 

 the shell of a tubicolous annelid. 



The plate illustrating this paper has been prepared by Mr. J. "W. 

 Tutcher, of Bristol, and Mr. G. W. S. Brewer, F.G.S., of Cheltenham, 

 for whose invaluable assistance I am deeply grateful ; while to 

 Major E. F. Becher, of Cheltenham, I am indebted, for the 

 photograph reproduced in the text on p. 580. 



EXPLANATION OF PLATE XLY. 



Figs. la,lb, &lc. Dentalium hexagonale, sp. nov. (p. 581). 



a=Specimen, X 2; 6= Transverse section, X 4; c=Portion of test 



enlarged. 

 Hemerae : oxynoti-armati. Locality : Gasworks, Gloucester. 

 Colin. : L." Eichardson. 

 2 a, 2 b, 2 c, & 2 d. Dentalium subtrigonale, sp. nov. (p. 589). 



a= Specimen, X 2; 6= Transverse section, posterior end, X 4; 



<? = The same, anterior end, X 4; <2=Portion of test enlarged. 

 Hemera: armati. Locality: Folly-Lane clay-pit, Cheltenham. 

 Colin. : L. Eichardson. 

 3a, 3b, 3c, & 3d. Dentalium oblongum, sp. nov: (p. 585). 



a = Specimen, X 2 ; b— Portion of test enlarged ; c= Transverse 

 section of anterior end, X 4 (about); d=The same, posterior end, 

 X 7 (about). 

 Hemera : striati. Locality : Bailway-cutting, near Cheltenham. 

 Colin. : L. Eichardson. 

 4: a, 4 6, & 4 c. Dentalium trigonale, Moore (p. 590). 



«= Specimen, X 2 ; b— Transverse section of the posterior end, X 2 



(a little more) ; c= Portion of test enlarged. 

 Hemerae: oxynoti-armati. Locality: Gasworks, Gloucester. 

 Colin.: L. Eichardson. 

 ha, 5b, 5c, & 5d. Dentalium trigonale, Moore. . 



' a=View of holotype, X 2 (a little more) ; 5=The same, natural size ; 

 c=View of ventral side of holotype, natural size ; d= Transverse 

 section, natural size. 

 Hemera: [armati]. ' Middle Lias.' Locality: Cam erton, near 

 Eadstock (Somerset). Colin. : Charles Moore, Bath Museum. 

 6 a, 6 b, & 6 c. Dentalium liassicuvi, Moore (p. 581). 



a=View of holotype (slightly enlarged); 6=The same, X 4 (about); 



c= Transverse section, X 4 (about). 

 Hemera: [armati]. Locality: Camerton, near Eadstock (Somer- 

 set). Colin. : Charles Moore, Bath Museum. 

 Fig. 7. Dentalium subovatum, sp. nov. (p. 587). Transverse section, X 6. _ 



Hemera,: [marmorecs], 'Zone of Ammonites angulatus? Locality 

 Eedcar (Yorkshire). Colin. : E. Tate, Museum of Practical 

 Geology, Jermyn Street. 



