DIASTOPOKA. 
135 
Pergens, the paii: on the left-hand side Tvonld be included in 
^esenteripora and the Entalophoridae, and the other part Tvonld 
he assigned to Diastopora as one of the Diastoporidae. 
The zooecial dimensions of the British specimens are not 
identical with the original type, hut they agree yery closely in 
general characters, having well - raised peristomes, which ai'e 
crowded and suhquincuncially arranged. 
LIST OF speci:mens. 
D. 419. A zoarium partly unilaminar and partly bilaniinar, with a ‘ zoarial 
lamina’ (on slide). Middle Chalk. Chatham. Gamble Coll. 
Figd. Xo. 8, p. 134. 
D. 3056. A fragment of a tubular zoarium, in flint. Middle Chalk. Chatham. 
Gamble Coll. 
rXBEPRESEXTED AXD DOUBTFUL SPECIES. 
1. acuta (d’Orhigny), 1 853. 
Syn. Bidiastopora acuta, d’Orbigny, 1853-4. Bry. Cret. p. 799, pi. 784, 
figs. 3-5.' 
,, ,, Marsson, 1887. Bry. Riig. : Pal. Abb. vol. iv. p. 17. 
,, ,, Pergens, 1890. Revision, p. 307, pi. xi. tig. 7. 
,, campkheana, d'Orbigny, 1853-4. Bry. Cret. p. 800, pi. 784, 
figs. 6-b. 
Char. — Zoarium of narrow, dichotomous branches. Zooecia fairly large. 
Peristomes arranged in transverse, oblique bauds, or irregular. 
Distrib. — Xeocomian: St. Croix, Vaud. 
2. echinata, Pocta, 1892. 
Syx. Diastopora echinata, Pocta, 1892. Mech. Koryc. Hory : Ceska Ak. Fr. 
Jos. Praze, sect. ii. p. 16, pi. i. figs. 21, 22. 
Char. — Zoarium unilaminar, in irregular cylindilcal mass. Zooecia slender ; 
rather crowded. 
Distrib. — Cenomanian : Rank, Bohemia, in Korycaner Schichten. 
Aff. — X early allied to D. escharoides, ^lich., hut with closer and 
more slender zooecia. Also allied to B. remensis, Per. 
3. corneti & P.), 1885. 
Syn. Bidiastopora corneti, Meunier & Pergens, 1885. Xouv. Bry. Cret. sup. : 
Aun. Soc. mal. Belg. vol. xx., Mem. p. 37, pi. ii. 
fig. 9. 
' The figure of D. acuta has resemblances to Borina or Siphoniotyphlus. 
