M. K. A. Zittel on Fossil Monactinellidce. 
307 
1. Scoliorhaphis cerebri for mis , Zitt. 
Sponge nodular or incrusting, with a convex surface, upon 
which project crests and tubercles of various forms, separated 
by mseandrically twisted and anastomosing depressions. The 
skeleton consists almost exclusively of rugged, vermiform, 
rather short spicules, with isolated smooth bacillar spicules. 
The original specimen of this species was contained in the 
palaeontological collection at Munich under the denomination 
u Amorphospongia , sp. nov.,” and conies from the Quadratus- 
chalk of the Sutmerberg. 
2. Scoliorhaphis anastomans , Zitt. 
Sponge nodular, perforated, consisting of thin contorted 
and anastomosing lamellae. Skeleton with tolerably long, 
vermiform, rugged spicules, with which simple bacillar spi¬ 
cules of various sizes and forms are intermixed in great 
quantities. 
$?fa</mtas-chalk of Linden and Ahlten in Hanover. 
Cliona, Grant. 
Vioa, Nardo ; Clionites, Morris ; JEntobia , Bronn. 
To this genus belong sponges which possess a skeleton 
composed of horny fibres and bacillar spicules, and which 
bore into shells and stones. In the interior of the bodies 
inhabited by them they form much-branched passages, which 
are in part narrowed and then again widened, so that thus 
they divide into chamber-like sections. They are connected 
with the surface only by cylindrical passages, which open by 
a small round orifice. 
Notwithstanding all my endeavours, I have never suc¬ 
ceeded in finding spicules in the above-described cavities 
of fossil bivalve and univalve shells; but the passages agree 
so well with those of the existing Clionce , that they have 
long since been referred to this genus of sponges. The 
boring sponges seem most frequently to seek out the shells of 
Ostrea , Pec ten, Inoceramus, Placuna, and Avicula ; but I have 
also observed them in Pectunculus , Venus, and Cytherea , and 
in Cerithium giganteum. 
Hancock has published detailed investigations upon the 
living species of Cliona *. 
From the occurrence of perforations, the existence of the 
genus may possibly be traced back even to the Silurian 
formation; but the perforations in Cretaceous Ostrece and 
* Ann. & Mag. Nat. Hist. 1840, vol. iii. p. 321-347, and vol. iv. 
pp. 355-357; and Nat. Hist. Trans. Northumberland and Durh. 1808. 
