explanations" of plates. 
PLATE I. 
Fig. 1. Actinopora hrongniarti (Edw.). Upper Chalk : Dover. 
Incrusting on Echinocorys scutatus. x 10 dia. J. S. 
Gardner Coll. [D. 3098.] 
Fig. 2. Actinopora hrongniarti (Edw.), var. cretacea, d’Orb. Upper 
Chalk : South of England, x 10 dia. Butler Coll. 
[D. 4477.] 
Fig. 3. Actinopora disticha (Hag.), var. gaudryana (d’Orb.). Upper 
Chalk ; loc. ? x 10 dia. Morris Coll. [D. 4582.] 
Fig. 4. Actinopora complanata (Kom.). Copper Chalk : Bromley. 
X 10 dia. Bowerbank Coll. [D. 3109.] 
Fig. 5. Actinopora complanata (Edm.). Middle Chalk : Chatham. 
X 10 dia. Vine Coll. [D. 2695.] 
Fig. 6. Actinopora complanata. (Eom.), var. suhdisciformis^ d’Orb. 
Middle Chalk : Chatham, x 7 dia. Gamble Coll. 
[D. 4245.] 
Fig. 7. Actinopora convexa (Eom.). Upper Chalk : loc. ? Fig. 7a, 
the upper surface of the zoarium, x 10 dia. ; Fig. 76, the 
zoarium from the side, nat. size. Morris Coll. [50,460.] 
Fig. 8. Discocavea irregularis (d’Orb.). Middle Chalk : Chatham. 
Fig. 8a, the upper surface of the zoarium, x 10 dia. ; 
Fig. 86, the zoarium from the side, nat. size. Vine Coll. 
[D. 2757.] 
Fig. 9. Discocavea irregularis {d^Orh.). Upper Chalk : loc.? Fig. 9a, 
the upper surface of the zoarium, x 7 dia. ; Fig. 96, the 
zoarium from the side, nat. size. Morris Coll. [50,468.] 
Fig. 10. Discocavea longiradiata. Lower Chalk : Southern Pit. 
Fig. 10a, the upper surface of the zoarium, x 3 dia. ; 
Fig. 106, part of the same specimen, x 10 dia. Capron 
Coll. [D. 4587.] 
