Mr. H. J. Carter on Teichonellidae. 35 



responding parts in figs. 1-5 : a, cartilage-pit ; b, b, sockets for 

 insertion of cardinal margin of opposite valve ; c, c, " teeth," or 

 dental ridges ; d, d, oblique diverging impressions. 



Fig. 6. Nuculcma attemtata, Fleming, interior of part of left valve ; natu- 

 ral size. Roscobie Quarry, near Dumfermline ; shale above the 

 Ttoscobie Limestone, Lower Carboniferous Limestone group. 



Fig. 7. The same, enlarged twice. 



Fig. 8. Nucida gibbosa, Fleming, interior of left valve ; natural size. 

 Roscobie Quarry, as before. 



Fig. 9. The same, enlarged twice. The same letters refer to correspond- 

 ing parts in figs. 6-9 : a, cartilage-pit ; b, posterior teeth ; c, 

 anterior teeth. 



I am indebted for the above excellent drawings to my col- 

 league, Mr. B. N. Peach. 



V. — On Teichonia, a tieio Family of Calcareous Sponges ^ 

 with Descriptions of two SjMcies. By H. J. Caeter, 

 F.K.S. &c. 



[Plate II.] 



Usually the excretory canal-systems of the Calcispongise 

 open into a common cavity, called by Dr. Bowerbank the 

 " cloaca," which discharges itself at one or more apertures ; 

 hence such Calcispongise are tubular or sacciform respectively. 

 But we should have a very imperfect idea of the Calcispongige 

 if we assumed that this was invariably the case, as Haeckel 

 appears to have done, and therefore has based his classifica- 

 tion upon the sacciform character alone, as will be seen in 

 the "General Observations" at the end of this communica- 

 tion ; for there are some species which have no cloaca, but 

 are muriform or foliate, and whose excretory canal-systems 

 open directly upon the surface, of which the following descrip- 

 tions may serve as illustrations. 



Teichonellidae (Tet;\;o9, a wall), new family. 

 Character. Vallate. 



Teichonella, nov. gen. 



Generic characters. Vallate or foliate, without cloaca. 

 Vents numerous, confined to the margin or general on one 

 side of the lamina only ; naked. 



• 1. Teichonella prolifera, n. sp. (PI. 11. figs. 1-5.) 



Calcisponge. Foliaceous, vertical, plicate, proliferous. Co- 

 lour yellowish white. Lamina thick ; margin round or ob- 



