179 



EXPLANATION OF PLATE. 



Fig. I. M iciosch'rodenna hirsnttiin, sp. n. ^ natural size. 

 la. Outer or poral surface. Natural size. 

 lb. Section, x 3. 



ic. Two monocrepid desmas, x 100. 

 i({. Oxea, X 100. 



IC. Sigmaspires, x 700. (The terminal thickenings do not 

 reallv exist, and disappear on focussing). 



Fig. 2. Discodcniiid luitcileu^is, sp. n. § natural size. 

 2a. Outer or poral surface, x 80. 

 26. Inner or oscular, X 80. 

 2C. Phyllotriaene of poral surface, x 100. 

 2d, t\ Discotriccnes of oscular surface, x 100. 

 2/. Small tyle, X420. 

 2g. Oxea, X 420. 

 2h. Style, X 420. 

 2j. Microxea, x 700. 

 2k. Microstrongyles, x 700. 



Fig, 3. Discodeniiia natcdcnsis, a much worn specimen, 

 f natural size. 

 3«, b. Tetracrepid desmas, x 100. 

 3c. Style, X 100. 

 3flf. Microstrongyles, x 700. 



Fig. 4. Section of wall of specimen drawn in Fig. 3, slightlv 

 enlarged, showmg a patch (lighter in shading) of Trip- 

 toleinus inccrtus, sp. n., in the midst of the Lithistid 

 skeleton of the Discodeniiia. 



Figs. ^a-d. Centrotriaenes, x 100. 

 46*. Microxea, x 100. 

 4/. Metaster, x 1625. 



