﻿154 Proceedings of the Boyal Physical Society. 



the species described from Europe, India, and Australia. 

 Doubtless two of the American species described by Dr 

 E. 0. Ulrich are without diaphragms (viz., S. angularis and 

 Steno'jpora (?) signata), but this is the only resemblance, the 

 other characters being quite different.^ 



The same remark applies to S. spissa, Eogers,^ another 

 form in which the diaphragms are absent. Apart from this 

 absence of diaphragms, reference to the figures given here 

 shows that the other structural features, such as the shape, 

 the size, and number of the swellings of the walls, etc., are 

 quite characteristic. 



Comparison with the species of Stenopora (?) described by 

 the older authors is much more difficult, as there is only the 

 external appearance to go by. Of the two species described 

 from Eussia by Lonsdale, Stenopora " spinigera is placed by 

 most authors in the genus Geinitzella, Waagen and Wenzel 

 (now Batostomella, Ulrich). This is probably its correct 

 position, as, according to Lonsdale's description, the walls do 

 not exhibit the moniliform structure characteristic of the 

 genus, or rather, he did not observe the corresponding con- 

 tractions of the tubes. S. crassa has also been removed to 

 the genus Geinitzellci ^ by some palaeontologists, but in this 

 case there seems to be nothing to prove the non-validity of 

 the generic attribution of the species, as Lonsdale distinctly 

 says in his diagnosis of the species, that " contractions are 

 occasionally visible in the bent portions " [of the zogecia],* 

 and on Fig. 12 a of the accompanying plate there is an un- 

 doubted attempt at showing them. It is necessary to give 

 these details, as the external characters of S. hrucei bear 

 some resemblance to those of S. crassa, Lonsdale ; but the 

 former differ from the latter in having twice as many zosecia, 

 and a more distinctly differentiated mature region. 



In 1875 Professor Toula described from the Permo- 



1 Geol. Surv. Illinois, vol. viii. pp. 439, U6, 1890. 

 - Kansas Urdversity Quarterly, Ser. A, Jan. 1900. 



3 Waagen and AVenzel, loc. cit., p. 884. See also A, Stuckenberg. "Die 

 Korallen und die Bryozoen der Steinkohlen-ablageningen des Ural und des 

 Timau," Mem. du Comite Geol. de Russie, vol. x., 1895, p. 227. 



^ MurchisoiVs Russia y p. 632, Plate A, figs. 12, 12 a. 



