STILL FOUND IN A LIVING STATE. 359 
Fossil in the chalk marls of Oran; recent in the Cattegat near 
Tjorn. Diameter 71, — 3;'". 
15. Actinocyclus denarius. Syn. Act. denarius, 1838. 
Fossil in the chalk marls of Oran; recent in the Cattegat near 
Tjorn. Diameter of dises 3, — zy!" 
16. Actinocyclus undenarius, n. sp. A. sepimentis carens, disci sub- 
tiliter punctati radiis undecim. 
Fossil in the chalk marls of Oran and Zante; recent in the Catte- 
gat near Tjorn, and in the bay of Christiania, Norway. Diameter of 
dises 2, — x4". 
17. Actinocyclus bisenarius, n. sp. A. sepimentis nullis, disci subti- 
liter punctati radiis duodecim. 
Fossil in the chalk marl of Oran; recent in the Cattegat near 
Tjorn. Diameter of the fossil 4;'", of recent 2;'". 
18. Actinocyclus (Actinoptychus) duodenarius, n. sp. A. septis inter- 
nis in duodecim loculos divisus, disci subtiliter punctati radiis totidem. 
Observed only recent in the water of the North Sea near Cux- 
= 1 i bam df 
haven. Diameter aea—zo° 
19. Aetinocyclus quindenarius, n. sp. A. sepimentis nullis, disci sub- 
tiliter punctati radiis quindecim. 
Fossil in the chalk marl of Oran; recent near Tjérn. Diameter 
of the fossil 2,'", of the recent g, — 7,'". 
20. Actinocyclus (Actinoptychus) sedenarius, n. sp. Pl. VIII. fig. 2. 
A. septis internis in sedecim loculos divisus, disci subtiliter punctati 
radiis sedecim. 
Recent near Cuxhaven. Diameter of the shells 3,./" 
21. Actinocyclus (Actinoptychus) octodenarius, n. sp. Pl. VIII. fig. 3. 
A. septis internis in octodecim loculos divisus, disci subtiliter punc- 
 tati radiis octodecim. 
Recent near Cuxhaven. Diameter 3,'". 
29. Amphitetras antediluviana, n. sp. A. testula singula cubica ubi- 
que cellulosa, cellulis in faciebus lateralibus radiatis, angulis varie 
_ productis. 
Fossil in the chalk marls of Oran and Greece; recent near Tjorn. 
Diameter 7; — 7,"". 
A few days ago I found in the Greek chalk marls a second spe- 
cies of this genus, which has on the lateral surfaces parallel rows of 
cells, and may be distinguished as A. parallela. 
23. Biddulphia pulchella, Syn. Conferva biddulphiana, Engl. Bot.; 
Diatoma biddulphianum, Agardbh.; Biddulphia pulchella, Gray ; 
_ Biddulphia australis, Montagne. B. testule quadrate compresse 
processibus lateralibus ternis quinisve parvis, obtusis. 
