VON BUCH ON THE CYSTIDEA. ^l 



Note. — Pseudocrinites hicopuladigiti, figured by Mr. R. Garnet 

 in the 'Natural History of Staffordshire ' (fig. A. 8-13), copied in 

 the ' Athenaeum,' No. 803, fig. 10, and described by Messrs. Bennett 

 and Pearce, is manifestly a Cystidea resembling Caryocystites. An 

 ovarial orifice may be observed in the upper part, and beyond the 

 basal plates three rows of hexagonal plates rise one above another 

 to the completely enclosed summit. The specimen is in the Dudley 

 Museum, but the locality is not given. 



A species figured and described by Mr. J, Sowerby in the * Zoo- 

 logicalJournal ' (ii. 318) also probably belongs to this family. Five 

 long tentacula proceed from the mouth. A large ovarial orifice 

 may be observed at no great distance from the mouth, and a con- 

 siderable number of irregular plates surround, as in Sphceronites, 

 the spheroidal figure. It was discovered by Mr. Bigsby not far from 

 the falls of La Chaudiere on the Ottawa river in Lower Canada. 



D. T. A, 



DESCRIPTION OF THE PLATES. 



Plate III. 



Figure 1 . Caryocrinus ornatus, natural size, viewed from the side. 



a. Mouth. 



c. Base, and attachment of the stem. 

 e, e. Single arms. 



/,/. Pairs of arms. 



2. Ditto, seen from above. 



3. Sphceronites aurantium, natural size, viewed from the side. 



a. Mouth and proboscis, with the small anal orifice (d) ad- 



joining. 



b. Ovarial orifice closed with valves. 

 e. Attachment of the stem. 



d. Anal orifice*. 



4. Caryocystites granatumy natural size, viewed from the side. 



5. Caryocystites testudinarius, ditto. 



6. Hemicosmites pyriformis, ditto. 



7. Sycocystites angulosus vel SencAenbergii, ditto. 



8. Crypt ocrinites cerasus, ditto. 



9. Ditto, seen from above. 



* The same letters of reference apply to the remaining figures in this plate. 



