M. K. A. Zittel on Fossil Lithisfidce. 337 



surface with scattered Avart-Iike oscula. Skeletal corpuscles 

 curved, branched, the ends root-like ; main branches smooth, 

 with a few spinose processes. Surface-spicules with a short 

 pointed shaft, from the outer end of wliich three, bent, branched 

 arms issue horizontally. Arms flat, with processes and 

 branches on both mai'gins. Also minute flesh-spicules pointed 

 at both ends in great numbers. Two species. 



MacAndreicia azorica, Grray, Bow. Mon. pi. v. figs. 1-5. 

 MacAndrewia [CoralUstes) clavatella, Schmidt. 



AzORiCA, Cart. 

 (Aim. & Mag. Nat. Hist. ser. 4, vol. xii. p. 442.) 



{Recent.) Sponge cup-shaped, strongly folded, with a short 

 stalk ; on the inner surface wart-like oscula ; on the outside 

 fine pores ; skeleton consisting of small, smooth, irregularly 

 branched siliceous elements, with root-like branches at the 

 ends ; surface-layer with corpuscles of similar form, only 

 differing from those of the interior by isolated knots, Flesh- 

 spicules bacillar. 



Azorica Pfeifferce, Cart. 



Leiodermatium, 0. Schmidt. 

 (Atl. Sp. p. 21.) 

 {Recent.) Like Azorica^ but the oscula on the outside. 

 Leiodermatium lynceus^ Schmidt. 



Verruculina, Zitt, 



Spongia p. p., Phil. 

 Manon p.p., Rom., Reuss. 

 Ckenenchpora p. p., Mich., Rom., Gein, 



Sponge irregularly funnel-, bowl-, ear-, or leaf-shaped, 

 often curved, attached by a short stalk or sessile, margin 

 rounded off. Oscula only on the upper ( = inner) surface, on 

 wart-like elevations. Lower ( = outer) wall with numerous 

 fine pores. From the oscula rather wide curved canals pene- 

 trate to about the middle of the thick wall, receiving innume- 

 rable capillary tubes from all sides. Rather finer canals run 

 inwards from the pores of the outer surface. 



By the numerous fine canals the small siliceous elements 

 are grouped into anastomosing fibres, which appear like a 

 vermiform tissue to the naked eye. Under the microscope 

 these fibres prove to be formed of small, elongated, bent cor- 

 puscles, with many longer and shorter root-like lateral 

 branches, closely interlaced by their lateral processes. Both 

 surfaces of the sponge-body are covered with an apparently 



Ann. & Mag. N. Hist. Ser. 5. Vol. ii. 23 



