PLATE 17. 
Fig. 1. 
101. 2. ChjEtetes lycoperdon. 
( Pag. 40.) 
1 a. The upper surface of a flat massive form. 
1 b. Figure showing the height of the same specimen. 
1 c. The lower surface of the same specimen. 
1 d. Section of a small hemispheric mass. 
1 e. Several columns enlarged. 
1 f. Openings of cells enlarged. 
1 g. A ramose specimen on limestone. 
1 h, i, k. Sections of the branches of several ramose specimens through the centre, and on one side of the 
centre, showing the arrangement of the cells. 
1 l. Several of the cells enlarged. 
Fig. 2. 418. 2. Favistella favosidea. ( Pag- 41.) 
2 a. A fragment of a large mass : cells natural size. 
2 b. Three of the cells enlarged, showing the double walls which coalesce at intervals. 
2 c. A small spheroidal mass of the same species. 
2 d. A section of a spherical mass of this species, showing the radiating cells. 
2 e. A small fragment showing the rays within the cells. 
2 f. Several of these cells enlarged, showing the rays, etc. 
Fig. 3. 
419. 1. BILATERALIS. 
(Pag. 41.) 
3 a. Posterior view, showing the shorter posterior side and oblique cup, which has about 48 rays. 
3 b. Anterior side of another specimen, showing the mode of increase by the addition of new l ays or lamella?. 
3 c. An enlarged view of the cup of another specimen. 
3 d. A longitudinal section, showing the internal characters. 
3 e. A young specimen, lateral view. 
3 /. Enlarged view of the cup, showjng the irregular union-of the lamella? in the centre. 
3 g. A large individual : view a little on one side of the anterior face. Kays 50 or more. 
3 h. An irregular form, apparently of this species. 
Fig. 4. 420. 1. Cyclolites rotuloides. (Pag. 42.) 
4 a, b. The upper surface of two individuals of different size. 4 c. Lateral view of the same. 
4 d. Base of another individual. 4 e. Several rays enlarged. 
