PLATE XIII. 
Fig. 1. Sparsicavea carantina, Orb. Middle Chalk : Chatham. A 
branch of which the upper part is in the form carantimt 
and the lower in that of francqana, x 10 dia. Vine Coll. 
[D. 695.] 
Fig. 2. Sparsicavea carantina^ Orb. Middle Chalk : Chatham. A 
branch with the radial ribbing indistinct, x 10 dia. Vine 
Coll. [D. 2623.] 
Fig. 3. Sparsicavea carantina, Orb. Middle Chalk : Chatham. A 
worn zoarium with the cancellate wall removed, x 10 dia. 
Vine Coll. [D. 698.] 
Fig. 4. Sparsicavea carantina^ Orb. Middle Chalk : Chatham. A 
branch of which the upper part has been cut down to 
show the maculae, x 10 dia. Vine Coll. [D. 721.] 
Fig. 5. Sparsicavea carantina^ Orb. Middle Chalk : Chatham. A 
branch of the form francqana^ x 12 dia. Gamble Coll. 
[D. 4071.] 
Fig. 6. Sparsicavea carantina, Orb. Upper Chalk : Croydon. A 
branch with gonocyst, x 10 dia. Old Coll. [D. 4479.] 
Fig. 7. Sparsicavea carantma, Orb. Middle Chalk : Chatham. A 
branch of form francqana with gonocyst, x 10 dia. 
Gamble Coll. [D. 432.] 
Fig. 8. Clausa francqana (Orb.). Upper Chalk : Kent. Part of 
a branch with bare proximal end, x 10 dia. Simmons 
Coll. [40,363.] 
Fig. 9. Clausa francqana (Orb.). Chalk : South-East England. 
Part of a fusiform branch with a short bare end, x 8 dia. 
T. Smith Coll. [D. 4564.] 
Fig. 10. Clausa francqana (Orb.). Middle Chalk : Chatham. Upper 
part of a zoarium with a bare distal end, x 10 dia. 
Gamble Coll. [D. 433.] 
Fig. 11. Clausa francqana (Orb.). Upper Chalk : Bromley. A 
branched zoarium with bare proximal end, x 9 dia. 
Simmons Coll. [D. 2840.] 
Fig. 12. Clausa francqana (Orb.). Middle Chalk : Chatham. A 
thin branch with long, narrow, bare proximal end, x 10 
dia. Vine Coll. [D. 2720.] 
Fig. 13. Clausa francqana (Orb.). Middle Chalk: Chatham. The 
distal end of a zoarium, with gonocyst, x 10 dia. Gamble 
Coll. [D. 437.] 
Fig. 14. Sparsicavea ivrighti^ n.sp. Upper Chalk : Bromley. Part 
of a stem, x 8 dia. Simmons Coll. [D. 2834.] 
Fig. 15. Clausa heteropora (Orb.). Middle Chalk ; Chatham. A 
branch, 10 dia. Vine Coll. [D. 2711.] 
Fig. 16. Clausa irregularis {Orb.). Upper Chalk: Salisbury. Branched 
fragment, x 10 dia. Vine Coll. [D. '2651.] 
Fig. 17. Sparsicavea wrightf n.sp. Chalk Powder : Slieve Gallion, 
CO. Derry. Fig. 17a, part of a stem, x 12 dia. ; Fig. 175 is 
the lower continuation of I7a, x 12 dia. J. Wright Coll. 
[D. 3277.] 
