PLATE XXXV. 



Page 



Fig. 1. Lymnorea mamillosa, Lamx. Natural size. Sbowing the upper surface. From 



the INIiddle Jura at Ranville, near Caen 184 



Fig. 1 a. The same. A portion of the upper surface of the same specimen, enlarged thirty 

 times, showing the irregular interspaces between the fibres, and in places an 

 open dermal layer of three- or four-rayed spicules. 



Fig. 1 b. The same. A portion of the fibre of the interior, enlarged seventy-two times, 

 showing fragments of three- and four-rayed spicules. The fibre is extensively 

 crystallized, and only the larger axial spicules are preserved. Drawn from a 

 transparent section of a specimen from the Inferior Oolite near Cheltenham. 



Fig. 2. Inobolia inclusa, Hiude. Natural size. From the Inferior Oolite near Chel- 

 tenham 185 



Figs. 2 a, 2 6. The same. Portions of the interior fibres of the same specimen, enlarged 

 seventy-two times, showing three- and four-rayed axial spicules. Drawn from 

 transparent sections. 



Figs. 3, 3 a. Stellispongia corallina, From. sp. Natural size. Two examples of this species 



from the Coral Rag at Lyneham, Wiltshire 186 



Fig. 3 b. The same. A portion of the interior fibres, enlarged seventy-two times, showing 

 relatively large axial tlu-ee- and four-rayed spicules, and smaller siuuous spicules 

 forming the borders of the fibre. 



Fig. 4. Sestrostomella niffosa, Hinde. Natural size. From the Upper Green Sand? at 



Vaches Noires, near Havre 188 



Fig. 4 a. The same. A fragment of the interior fibre, enlarged seventy-two times, showing 

 axial three- and four-rayed spicules, surrounded by smaller irregular spicules. 

 Drawn from a transparent section. 



Figs. 4 b-d. The same. Small irregular three-rayed or pitchfoi'k spicules of the fibre. 

 Fig. 4 6 represents two of them enlarged seventy -two times; figs, c and d the 

 same forms enlarged two hundred times. Drawn under the camera lucida from 

 the same transparent section as 4 a. 



Fig. 5. Sestrostomella clavata, Ilinde. A portion of the interior fibres, enlarged seventy- 

 two times, showing very distinctly a large axial four-rayed spicule. From the 

 Upper Green Sand at Vaches Noires, near Havre. Drawn from a transparent 

 section 188 



Fig. 5 a. The same. Another fragment of the interior fibre in the same microscopic section 

 as fig. 5, showing the spicular structure of the marginal borders of the fibre 

 with several small pitchfork and other irregular three-rayed spicules. Enlarged 

 seventy-two times. 



Fig. 6. Trachysinia aspera, Hinde. Seen from above. From the Middle Jura at Ranville, 



near Caen. Natural size 189 



Figs. 6 a, b. The same. Two fragments of the interior fibres, enlarged seventy -two times, 

 showing three- and four-rayed spicules of various sizes. Drawn from the same 

 transparent microscojnc section. 



