t»^ 



TRENTON LIMESTONE. 



89 



127. 1. ECHINO-ENCRINITES ANATIFORMIS (n. sp.)- 



Pl. XXIX. Figs. 4 a, b, c, d, e,f. 



Body composed of four series or ranges of plates ; basal or pelvic plates four, three of 

 them pentagonal, and one with the upper angle truncated ; second series hexagonal ; the 

 third series indistinct, those forming the summit not visible. Column short ; lower ex- 

 tremity very slender, and composed of joints which are twice or thrice as long as broad ; 

 in ascending, the diameter increases, and the joints are shorter, finally becoming flat rings 

 with prominent sharp edges, being nearly one half the diameter of the cup above. 



The summit of the specimen presents an appearance as if the original had been provided 

 with arms or tentacula, but there are no remains of them observable. 



Our species approaches very closely to those figured and described by H. Von Meyer 

 and VoLBORTH, as quoted by Von Buck in his paper on the Cystidea* ; and also those 



• Joamal of the Geological Society of London, No. 5, 1846. 



The accompanying illastration, fig. 1, is from this paper of M. voir Buch, and will convey a more definite idea of 

 the form of these bodies than the imperfect specimens thus far seen in our rocks. 



Fig. 1 a, the summit, with the mouth ; b, the ovarian aperture ; c, the base. 

 Fig. 2. Lateral view of a specimen, showing the ovarian aperture. 



Fig. 3 a, the base of the specimen ; .T 4, lateral view of the same. ^ 



Fig. 4. A portion of the column of the same species. 



Fig. 5, as above, is the Eehino-enerinites ttriatiu of Paitbeii. A small portion of the column is still adhering to 

 the body, and the side on which is situated the ovarian aperture a is much extended. 



(PaUeontology of Russia and the Ural Mountains, p^g. 29 & 30, pi. 1 & 27.) 



M. VoLBOBTH has recently discovered the vefy delicate tentacula of the Echino-encrinites {Bulletin de la Classe 

 Phya. Math, de S.-Petersbourg, Vol. iii. no. ). They are placed on the border of the buccal aperture, and do not 

 pierce the plates as in ordinary Crinoideans. These tentacula are not fimbriated ; and since, according to M. v. Buch, 

 the animal was provided with an ovarian aperture, they were not required for protecting the eggs, as in the true 

 crinoideans. The views of vow BvcH, however, do not entirely coincide with those of M. Volborth, who regards 

 this aperture as the anus.* 



* Sm boU OB pigs xiT. of M. PI VlBBIDIL's Otneral View of the Falmnoic Fauna of Ruaaia. 



[ Pal.«ontologt.] 



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