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Palaeontology of new-york. 
the two carboniferous genera Palachinus and Archceocidaris. Here are at least some links 
wanting, or the Cystideae in lower silurian times approached very rapidly to the echinidean 
character, if the apparent analogies be real ones. On the other hand, we pass from Hemicosmites 
to Cryptocrinites , which is a lower silurian genus, through the four succeeding genera, all of 
which are upper silurian ; and thence through Pentremites , which is both devonian and car¬ 
boniferous, to the Asteriada: and Ophiuridae. However close, therefore, the links may appear 
from structural affinities, there is a vast space of time between the occurrence of Agelacrinites* 
and the allied carboniferous genera ; and we might justly question the authority of Geology in 
such a case, if no intermediate types should be found. On the other hand, the links connecting 
these genera with Asteriadae are more numerous, and more closely connected in the order of 
time, and the direction may be true ; still there are a great number of forms yet to be known, 
which will perhaps modify any view at present given of the affinities of these genera. 
The following species of cystideans have been found in the shale of the Niagara group at 
Lockport; and I am indebted to the zeal of Col. E. Jewett of that place, for being able to 
present figures of well preserved specimens-)-. They offer very close analogies with those 
described by Prof. Forbes from Dudley in England ; but one of them, at least, is generically 
distinct, and the species are all quite dissimilar. 
Genus C ALLOCYSTITES (nov. gen.). 
[Gr. xaXos, pulcher, and mifng, vesica,] 
Body ovoid or sub-spheroidal, composed of four series of plates, three of which are con¬ 
spicuous, the fourth scarcely exposed ; basal plates four, unequal; costal plates or second 
series eight, third series probably of the same number, with a fourth series of small plates 
forming the apex. Ovarian orifice conspicuous, closed by a pyramid of triangular plates ; 
pectinated apertures in pairs on three parts of the body ; arms five or more, radiating from 
the apex and folded back upon the sides, resting in a broad shallow groove and distinctly 
projecting above the surface, composed of a double series of joints separated by a narrow 
groove ; articulated fingers attached to the arms in a double row, separated by the groove. 
Oral orifice below the apex, with an anal pore near it, and a porous tubercle above and a little 
on one side. Column short, composed of thin joints which diminish rapidly from the body. 
This cystidean, in its general characters and habit, is closely related to Pseudocrinites, and 
also to Apiocystites ; but it will be perceived at once that there are important differences in 
the structure of the body. It commences with four basal plates, as the genera mentioned ; but 
* This genus is used as defined by Prof. Forbes, and is not the Agelacrinites of Vanuxem. 
t Among the specimens of Caryocrinus collected at Lockport several years since, I discovered some specimens 
of these curious fossils; but they were so completely coated with pyritous shale, that I was unable to ascertain their 
structure, till the more fortunate discoveries which have brought to light the beautiful forms illustrated in Plates 50 
and 51. 
