ETHERIDaiA.— TOULMINIA. 139 



Genus ETHERIDGIA, Tate, 1865. 

 Etheridgia mirabilis, Tate. 



1865. Etheridgia mirabilis, Tate, Quart. Journ. Geol. Soc. vol. xxi. p. 43, t. 5. f. 4a, 4 6. 

 1877. Etheridgia mirabilis, Zitt. Studien, I Ab. p. 56; Neues Jahrbuch, p. 367. 



Sponge conical with truncated summit, the base depressed, convex, with short, 

 projecting cylindrical root-processes. At the summit is a circular aperture 15 mm. 

 wide. The sides of the cone are provided with circular or elliptical apertures about 

 4 mm. in diameter. The type specimen is 33 mm. in height and 40 mm. in width. 

 A compact dermal membrane extended over the base and sides. The interior 

 structure has been completely obliterated. The only specimens known are in the 

 Jermyn-Street Museum. 



Distribution. Spongarian zone of the Chloritic Chalk (Tate) = \]'p'peT Chalk: 

 Whitehead, near Belfast. 



Genus TOULMINIA, Zittel, 1877. 



ToDLMiNiA OBLiQDA, IHnde, n. sp. (Plate XXIX. figs. 7, la, 7b.) 



Sponge funnel- or cup-shaped. The only example is 48 mm. in height, and 50 mm. 

 wide at the summit. The cloacal cavity is 20 mm. in width near the upper margin ; 

 it appears to be without any definite wall. The wall is composed of irregularly 

 anastomosing folds about 1 mm. in thickness. The dermal membrane of the summit 

 of the walls has nearly entirely been removed ; the spicular mesh of the wall-plait is 

 irregular ; the distance between the nodes is "25 mm. 



Distribution. Upper Chalk : South of England {coll. T. Smith). 



TouLMiNiA JUEASSiCA, Hinde, n. sp. (Plate XXX. figs. 1, 1 a, 1 b.) 



Sponge inverted conical in form, with an oblique summit. The single specimen 

 is 63 mm. in height, and 40 in width near the summit. The cloaca appears to be 

 funnel-shaped, and bounded by a definite wall; it is 23 mm. in width at the upper 

 margin. The sponge is composed of anastomosing convolute wall-plaits, 1 mm. in 

 thickness. The spicular mesh of the wall, as seen in a transverse section, is regular 

 in disposition ; the nodes are octahedral, and '25 mm. apart from each other. No 

 dermal membrane has been preserved, probably owing to the weathering of the 

 surface. 



This species differs from the preceding in the well-defined character of the cloacal 

 cavity as well as in the disposition of the wall-plaits, as seen in transverse sections. 



This form is at present the only representative of the family of the Meandro- 

 spongidse from the Jurassic system. 



Distribution. Upper Jura : Eanden, Switzerland. 



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