PLATK IX. 
Fig. 1. Crisincc {Retlcrisiaa) pai:>i)mcca (Orb.). Middle Chalk : 
Chatham. Fig. la, obvoi*se edge of part of a zoarium, 
X 10 dia. ; Fig. lb, .side view of the .same, x 10 dia. : 
Fig. Ic, reverse edge of the same, x 10 dia. Gamble (’oil. 
[D. 3966. J 
Fig. 2. Reticrisina 'papyracca (Orb.), form complanata, Mai*s. MitldU* 
Chalk : Chatham. Part of reverse edge of a zoarium, 
X 12 dia. Gamble Coll. [D. 386.] 
Fig. 3. Crisina {Reticrisina) papyrace^t (Orb.). Chalk : I'l-eshwatoi-, 
Isle of Wight. A young zoarium, x 2 dia. Ganliier Coll. 
\B. 70.] 
Fig. 4. Crisina {Tervia) suhgracilis, Orb., var. depressa. Middle 
Chalk: Chatham. A young zoarium, x 12 dia. GambU* 
Coll. [D. 526.] 
Fig. 5. Crisina {Tervia) subgraedis, Orb. Upper Chalk : Gravesend. 
Part of a branched zoarium, x 18 dia. Vine Coll. [D. 968.] 
Fig. 6. Crisina marginata (Orb.). Middle Chalk : Chatham. Part 
of a zoarium, x 10 dia. Vine Coll. [D. 969.] 
Fig. 7. Crisina marginata (Orb.). Middle Chalk : Chatham. Part of 
another zoarium, x 10 dia. Vine Coll. [D. 969.] 
Fig. 8. Retecava cretacea (Edw.). Upper Chalk : Susse.x. Three of 
Lonsdale’s types. Fig. 8«, obverse edge of a branch, 
x 8 dia. ; Fig. 86, obverse edge of a lower part of the 
zoarium, x 8 dia. ; Fig. 8c, side view of a branch, x 8 dia. 
Dixon Coll. [D. 2966 ] 
Fig. 9. Crisina {Tervia) gamblei, n.sp. Middle Chalk: Chatham. 
Obverse face of a zoarium, x 12 dia. Gamble Coll. 
[D. 4069.] 
