40i PALJEONTOLOGY OF NEW-YOKK. 



Fig. 2 h. A small individual, preserving the thorax and the maxillary portion of the buckler, the glabella 

 being separated. Specimens of this kind are not rare among the young individuals. 



Fio'. 2 i. The maxillary shields, as they frequently occur in the slate, separated from any other part of 

 the fossil. The position and partial form of the base of the eye is clearly distinguishable. 



Fig. 2 k. A single maxillary shield of this species. 



It is impossible, from the slender and fragile nature of these portions of tlie fossil, to 

 decide whether the suture continues entirely across the front of the glabella, or is interrupted 

 as in other species of Calymene. The specimen 2 i, shows a continuous slender fillet 

 in front; but this may be joined to the lateral portions by sutures, since the specimen fig. 

 2 k terminates as in Cahjmene senaria. 



Position and locality. It has already been observed that this species is more abundant in 

 the Utica slate than elsewhere, being in fact the only trilobite usually seen in that rock. 

 Large surfaces of tiie lamina; are often almost entirely covered with the fragments and 

 more or less perfect individuals. The most prolific localities are Coldspring, on the Erie 

 canal, Montgomery county ; Oxtungo creek, above Fort Plain ; Martin's Hill, near 

 Amsterdam ; Turin, Lewis county ; and less abundantly at Utica and numerous other 



localities. (State Collection.) 



Plate LXVII. 



Jltops trilineatus. Emmons, Tac. System, pag. 20. 

 — — Id. Agr. Report, pag. 64. 



Fig. 4 a. The buckler, with a few of the articulations of the thorax. The specimen is very much 

 compressed, and the crust removed. It is imbedded in a gritty micaceous slate, and in such a 

 condition as to render it somewhat obscure. The form of the buckler, with the lobate 

 character of the glabella, leave no doubt of the true nature of the fossil. 



Fig. 4 A. A specimen of the same fossil, presenting nearly the entire length of the individual ; the 

 form and markings of the buckler are obscure, but still visible, and evidently identical with 

 the fossil from the Utica slate. 



Fig. 4 c. An iuiprcssion of the body of this fossil, showing the indentations produced by the short 

 spines upon the back. 



Fig. i d. A. portion of the same enlarged, showing the impressions of the fine granulations of the crust. 



Fig. 4 e. This fragment preserves an impression of a part of the central and one lateral lobe of this 

 species. ( See Emmons' Tacnnic System, pag. 19, pi. 2, fig. 3; and Agricultural Report, 

 pag. 63, pi. 14, fig. 3. ) 



These specimens are all in the thinly laminated, folded, and partially altered slates, on 

 the east side of the Hudson. Tire occurrence of these fossils is sulhcient evidence of the 

 age of the strata, without the evidence furnished in the structure of the country as presented 

 in the sections. This species likewise occurs in the unaltered slates of the Hudson-river 

 group, in Lewis, Jeficrson and Oswego counties. 



