Fossil Beticulate Sponges. 471 



duce gentle undulations in the tube. The finer reticulating striae, if 

 ever existing, have been removed by maceration. 



The specimen has a length of 70 mm., and the two diameters of 

 the compressed specimen are 13 and 25 mm. respectively. 



Formation and locality. In the Chemung group; Ithaca, N. Y. 



DlCTYOPHYTOX BACULUM, 91. Sp. 



Cup prismatic, distinctly octagonal, the side being flat or slightly 

 concave, attenuate toward the base; very gradually enlarging from 

 the base to a point above the middle, above which the tube is more 

 rapidly expanding. Base unknown. 



Surface marked by strong longitudinal and transverse striae, between 

 which are other striae of two degrees of strength, which separate the 

 surface into quadrules of finer reticulations. 



The specimen described, which is imperfect below, has a length of 

 150 mm., and it has probably been more than 200 mm. in length in 

 its original condition. At the lower part of the specimen as preserved, 

 it measures in its two diameters 22 and 30 mm. respectively. Its 

 greatest diameter in the upper part is 44 mm. 



Formation and locality. In the sandstone of the Chemung group ; 

 found loose at Wellsville, Alleghany county, N". Y. 



DlCTYOPHYTON PARALELLUM, n. Sp. 



Cup prismatic, very gradually enlarging, octagonal in transverse 

 section, but with the angles subdued; intermediate spaces slightly 

 convex. Base unknown. 



Surface finely reticulate. 



The specimen is an impression of the exterior in argillaceous sand- 

 stone, having a length of 130 mm., and the divergence of the angles 

 limiting the sides is less than one mm. 



Formation and locality. In the Chemung group ; precise locality 

 unknown. 



DlCTYOPHYTOK COETKADI. 



Plate 18, Figs. 3, 4, 4a. 



Dictyophyton Conradi, Hall. Sixteenth Ann. Rept. State Cab Nat Hist 

 p. 89, pi. 5, fig. 2; pi. 5 a., fig. 2. 1863. 



Cup subturbinate, slightly curved, flattened; transverse section 

 octagonal, having the proportions of about as two to three, and in 

 the upper part where compressed, about as three to eight. Base at- 

 tenuate, somewhat rapidly expanding above, increasing from 12 mm. 

 near the base to 45 mm. near the summit in the distance of 210 mm.' 



The upper part of the tube as preserved, is marked by strong pro- 

 tuberances produced by the depression and elevation of the surface 

 between the angles. Entire surface reticulate by longitudinal and 



