154 DlCTYOSPONGID^ 



Clatiirospongia caprodonta, sp. nov. 



Platk I,, Figs. 8, 9. 



Sponge slender, elongate obconical, gradually enlarging from an acnte 

 }>ase to the aperture, the rate of expansion being the most rapid over the 

 earliest one-third of the length. Surface faintly subprismatic, with low nodea 

 at the intersection of the primary spicular bands. 



Upon the single specimen observed, which is an internal cast, the reticulum 

 shows twelve longitudinal spicular ridges which, with the intersecting horizon- 

 tal ridges of about the same size, form large primary quadrules. Over the body of 

 the cup these measure about 13 mm. in width and 19 mm. in length, making a 

 comparatively large qiiadriile which was evidently very shai-ply defined over 

 the entire cup, except at the base and about the aperture. The angles of 

 these quadrules bear pronoiinced nodes, not so highly developed as in Hydno- 

 ceras, but indicating a tufted projection of the spicules, undoubtedly accom- 

 panied by a strong lamellar spicular band along the primary vertical and hor- 

 izontal ridges. These ridges and nodes are somewhat obscured by the 

 secondary reticulation, the entire surface being covered with meshes measur- 

 ing about 2 mm. on a side, the intermediate reticulation being virtually lost. 



The cup has an entire length of 185 mm. and an apertural diameter of 

 63 mm. Its diameter at 50 mm. from the apex, is 38 mm., and at 125 mm. 

 irom the base, it is 57 mm. 



Locality. In the sandstone of the Waverly group, at Portsmouth, Ohio. 

 (Collection of the School of Mines, Columbia University, New York.) 



THYSANODICTYA, gen. nov. 

 (For description see page 125.) 



Thysanodictya expansa. Hall (sp.). 



Plate liii, Fig. 3. 



1882. Phragmodictya expansa,Yl.i\\\ Notes on the Family Dictyospongidse ; 



Expl.pl. 19, fig. 10. 

 1884. Ectenodictya expansa, Hall. Thirty-fifth Ann. Rept. N. Y. State Mus. 



Nat. Hist., p. 475, pi. (19) 20, fig. 10. 



The original specimen of Ectenodictya expansa is a portion of a very large 

 basal disc or diaphragm, representing a species of those fonus occurring 

 abundantly in the Chemung sandstones for which we have erected the genus 

 TiiYSANODicTYA. The s^tccies is HomeAvhat irregularly nodose over the surface 



