72 



Henry Woodivard — Neiv British Cystidean. 



also the same genus. The number of plates is different in the 

 English, Canadian, and New York species, but this does not matter 

 in such a genus of Cystideans as this. Since my Decade was 

 published, we have collected several additional specimens of A, 

 Huxleyi, but, unfortunately, none of them give any new information. 

 They are all imbedded in the rock, and all show the same, the concave, 

 side. The four species — Ateleocystites Huxleyi, Billings, Lower Sil. ; 

 Placocystites Forhesianus, De Koninck, Upper Sil.; Anomalocystites 

 cornutus, Hall, Upper Sil. ; Anomalocystites disparilis, Hall, Devonian 

 — are all composed of a limited number of plates, not arranged in 

 regular series, their bodies convex on one side and concave on the 

 other. The first three have the plates transversely striated in a 

 peculiar manner, and most probably good specimens of the fourth 

 would show the same surface character. This striation is of the 

 same kind in all, and differs in aspect from that of any other 

 Cystidean genus known. ^ It is so peculiar that it appears to be 

 near a sort of a group character, so to speak, like the scale-markings 

 of some of the Crustacea. These points of agreement are of such 

 a nature that, although none of the species have been as yet de- 

 scribed on good specimens, they seem quite sufficient to prove that 

 they are congeneric. E. Billings. 



Montreal. 

 We subjoin figures of the upper and under sides of this remarkable 

 Cystidean, for the elucidation of which we now possess a very fine 

 series of specimens, many of which have been collected by C. Ketley,. 

 Esq. The original of Fig. 1 was obtained by J. Gray, Esq., of Hagley. 

 Ateleocystites Huxleyi, '&^\ixnga= Placocystites Forhesianus, De Koninck. 



Fig. 1. Convex side, showing the so-called "anal plate" (a), and the ovarian pore 

 (5), the base of the tentacles {f, t), and the point of attachment for the stem («). 



,, 2. Concave side, showing the tentacles {t, t). 



,, 3. View of the lower extremity of the body, showing the attachment of the stem (s). 



,, 4. View of the top of the body, showing the points of attachment for the arms 

 or tentacles {t, t). 



„ 5. Portion of stem near the body : drawn from a specimen having a portion of 

 the stem still remaining attached. 



„ 6. a, b, c. Three views of a small tapering stem, found detached, but having 

 the same characteristic sculpture visible upon its joints observed in Ateleo- 

 cystites. Probably the lower extremity of the stem. 



„ 7. One of the arras, or tentacles, drawn from a specimen, having the arm still 

 attached to the body. 

 (All the above specimens are in the British Museum, and were obtained from the 

 Wenlock Limestone, Wren's Nest, Dudley.) 



^ Compare the ornamentation of Ateleocystites with the plates of Turrilepas 



