96 REPORT— 13868. 
4, Smilotrochus angulatus, Duncan. 
The corallum is conical, hexagonal, slightly curved at its very fine inferior 
extremity. It is broad superiorly, and has six prominent angles, and is 
compressed slightly. The septa are fine, unequal, and each plane between 
the angles has a system of four cycles. The columellary space is large. 
Height # inch. Breadth } inch. 
Locality. Upper Greensand of Cambridge. 
In the collection of James Carter, Esq. 
Genus OnNcHOTROCHUS. 
Numerous specimens of a species of this genus are in the possession of 
James Carter, Esq. and the Rev. T. Wiltshire. The species has great resem- 
blance to the lower part of Onchotrochus serpentinus, nobis. A careful ex- 
amination of sections and calices proves that there is no columella, that the 
inner ends of the septa produce a false one, and. that the styloid appearance 
is due to fossilization. 
Onzhotrochus Carteri, Duncan. 
In the young corallum there is a flat and round expansion at the base, by 
which it was attached to foreign substances; but this is lost as growth proceeds. 
The corallum is either straight or slightly curved, is tall, very slender, conico- 
cylindrical, clavate, and enlarged here and there. Unworn specimens are 
more or less angular in transverse outline. The coste are angular projec- 
tions, extend from base to calice, are subequal, wide apart, and are connected 
and covered with a fine pellicular epitheca, which readily disappears. Growth- 
markings yery common. The calice is circular and shallow. The septa are 
short at the wall, and wedge-shaped; they are rounded inferiorly, and do not 
extend far inwards. There are twelve septa, and they are subequal. The 
septa in sections often appear equal, and their inner ends are joined, and the 
axial space is filled up by a deposit of coral-structure. But the reverse is 
the case occasionally, and the irregularity of the septa may be well seen. 
The septa are continuous with the coste. 
Height 3-2-1 inch. Diameter of calice 54, inch. 
Locality. Cambridge Greensand. 
In the collection of James Carter, Esq. and Rey. T. Wiltshire. 
The discovery of better specimens may perhaps lead M. de Fromentel to 
consider his Stylotrochus, which so resembles this form, to be of the same 
genus. 
Genus CrarHopnors, Michelin. 
This genus has the usual characters of compound Astreine; but the dis- 
sepiments act as tabulz, and shut in the calice below, just as in some of the 
Liassic [sastree. There is no columella*. Curved dissepiments are not 
noticed; and the family of the genus must remain unsettled, for the minute 
structure is clearly tabulate. The genus flourished in the Lower and Middle 
Oolites; and the only Cretaceous species is that under consideration, and 
which has been described by D’Orbigny from the Craie Tuffen, Les Martigues 
—Cyathophora monticularia, D’Orb., sp. 
The septa are rather thick. There are three cycles, but the third is often 
deficient in one or two systems. 
Locality. Haldon. 
In the collection of the Geological Society. 
* See remarks on Liassic Jsastree. 
