NIAGARA GHOUP. 



227 



This very interesting species is found in all stages of growth, and in all varieties of aspect 

 and surface marking. I have in my collection specimens from the size of a pea, to one of two 

 inches in length and an inch and three-fourths in its greatest diameter ; the intermediate 

 ones present much variety in form, from elongated ovoid, to globose, and sometimes almost 

 oblate spheroidal forms. This variety of form is sometimes caused by the presence or absence 

 of some plates at the base of the arms, above the scapulars, and sometimes by the development 

 of the plates progressing more rapidly in a lateral than in a longitudinal direction. 



Prof. Troost has enumerated five species as occurring in Tennessee : these are the Caryo- 

 crinus meconideus, C. hexagoiius, C. granulatus, C. insculptus, C. globosus ; while the C. 

 ornatus is not mentioned. It seems scarcely possible that this species, so common and abundant 

 in New-York, should not occur in Tennessee ; since the association of the genera named is 

 similar to Uiat in New-York, and, as cited previously, ten species of Eucalyptocrinus are 

 found in the same strata. The study of the five distinct sjiecies of this genus offers a most 

 delightful task. 



Position and locality. This .species is very abundant at Lockport and vicinity, and is not 

 uncommon at Rochester and Sweden in Monroe county, and has been found as far east as 

 Wolcott in Wayne county. Its greatest development, however, was in the vicinity of Lockport ; 

 and from other evidence, this was a favorable position for the growth of many species of this 



family. (State Collection.) 



Genus MELO CRINITES (Goldfuss). 



Columna teres, canali tereti vel quinquelobo perforata, brachiis auxiliaribus. . . . ; pelvis articulis 

 quatuor; costales primarii et secundarii quini, hexagoni, sibi invicem impositi ; intercostales 

 quinque, hexagoni costalibus imposits, hexagonae ; interscapulares quaterni, in oris regione 

 quinque ; brachice quinque ; os in latere verticis. 



The characters of the fragment described below, so far as can be ascertained, correspond to 

 those of this genus of Goldfuss. The anomalous feature of four pelvic plates succeeded by 

 five costals, is met with in no other crinoid ; and having only the plates of these two series 

 remaining, they furnish sufficient evidence for the reference to this genus. 



Of the two species described by Goldfuss, one is cited from the Moimtain limestone, and 

 the other from the Transition limestone. 



Melocrinites hieroghjphicus, and J\[. lavis, Goldfuss, Petrefacta Germania, Vol. i, pag. 197, pi. Ix, figs. 1 and 2. 



