142 PALEONTOLOGY OF NEW-TOEK. 



Genus LIMARIA (Steininger). 



Small, ramose ; coralla quite solid, cells with a subtriangular aperture ; calicles none. 



I have included under this genus a single species which is not ramose ; this one has the 

 internal structure and form of aperture which characterizes the ramose species. The cells in 

 different species open by a subtriangular or transversely extended sinuate aperture ; the tubular 

 cell is flattened near the aperture, and angular below as shown in transverse sections of the 

 stems. With the exception of the form of cell and aperture, their structure and mode of 

 growth differ scarcely at all from species of the preceding genus. It differs from the two fol- 

 lowing genera, in having no intercellular septate spaces. Worn specimens of Limaria are 

 scarcely distinguishable from Ch^tetes or Favosites. 



Two species of this genus are recognized by Mr. Lonsdale in the Wenlock limestone of 

 England, and we have three species in the Niagara group. 



531. 1. LIMARIA RAMULOSA (ti. sp.). 



PL. XXXIX. Fig. 4o-d. 



Compare Limaria dathrata, Steininger, Mem. See. Geol. France, i, 339, t. 20, f. 6, 1834. 

 — — Lonsdale, Sil. System, pag. 692, pi. 16 bis, fig. 7, 7 6, 1839. 



Coral ramose ; branches cylindrical or compressed, equally bifurcating or sometimes irregu- 

 larly trichotomous ; apertures of the cells sinuous, or subtriangular from wearing, closely 

 arranged ; internal structure of stems prismatic. 



I have separated this species from L. dathrata, which it greatly resembles from the uniform 

 close arrangement of the apertures of the cells, which are likewise less transversely elongated 

 than in specimens from Dudley. A single fragment among several specimens from Dudley has 

 the characters possessed by the Niagara species, but it is at the same time very different from 

 the larger number of specimens from the same locality. Until we know to what degree these 

 variations may extend, it seems more satisfactory to place the Niagark specimens under another 

 designation. 



Fig. 4 a. A single bifurcating branch of this species, somewhat worn. 



Fig. 4 5._A fragment which is trichotomous. 



Fig. 4 c. The surface enlarged. 



Fig. 4 d. The end of a stem enlarged, showing the structure. 



Worn specimens of this species may be readily mistaken for some of the preceding or fol- 

 lowing forms ; but by a careful examination, the apertures of the cells will always be found 

 characteristic. 



Position and locality. In the lower part of the limestone at Lockport, Niagara county. 



