290 NEW YORK STATE MUSEUM 



that species H. b 1 a i n v i 1 1 i i differs in its much more rapidly 

 iDranching zoarium and consequent shorter cells, producing a fuller 

 and denser stock. 



Middle Devonic. Gaspe Basin, P. Q. 



CORALS 

 Pleurodictyum lenticulare Hall var. laurentinum no v. 



Pleurodictyum lenticulare is a species of the Helder- 

 "bergian (New Scotland) fauna characterized by its very large and 

 few cells, the walls of which are strongly marked by nodose and 

 T^roken septa. A central cell, hexagonal in form, is bounded by 

 .six others and it often happens that the development of this spe- 



Pleurodictyum lenticulare var. laurentinum 



cies does not pass this primitive expression. The form before us 

 lias the same form and size of cells which are marked by radial 

 nodose and denticulated septa, these being most prominent -and 

 most irregular at the base. The lenticular corallum however grows 

 to larger size, showing three cycles of cells about that which may 

 1)6 taken as central. In the measurements of the cells the New 

 York and the Gaspe forms are alike. 



Lower Devonic. Grande Greve and Perce rock, P. Q. 



GRAPTOLITES 

 Chaunograptus gracilis nov. 



A shell of Leptostrophia magnifica Hall has afifixed 

 to it an irregularly branching black conchiolinous repent fossil which 

 in structure and substance seems to be congeneric with the peculiar 

 organism described and figured by Hall as Dendrograptus 

 (Chaunograptus) novellus from the Waldron (Niag- 

 aran) fauna [Geol. Sur. Ind. nth Rep't. 1881. p. 225, pi. i, fig. i, 

 2; before in Alb. Inst. Trans. 1879, v. 10, abstract, p. 2]. A com- 



