14 
THEOj^OID^. 
Al'FIJriTIES. 
The essential feature which distinguishes this ‘ species ’ from the 
previously described members of the genus is its uniserial rays. 
D’Orbigny regarded this character as of generic importance and 
founded the genus TJnituhigera . 
Woodward’s name B. radiata can hardly be accepted, as it was 
explained only by a practically indeterminable figure. 
The Cenomanian form, the A. suhdisciformis (d’Orbigny), has 
sinuous, long, crowded rows, which at first sight appear to dis- 
tinguish it from the Senonian form ; but some of the specimens 
from Chatham agree so well with the specimen figured by von 
Eeuss as subdisciformis that, in spite of the difference in age, I feel 
constrained to unite them, leaving the Cenomanian form as only 
a varietv. 
LIST OF SPECIMENS. 
British. 
D. 3109. A group of zoaria of the typical, long-spoked variety attached to 
Echinocorys scutatus, Leske. Upper Chalk. Bromley, Kent. 
Bowerbauk Coll. Figd. PI. I. Fig. 4. 
D. 2695. A young zoarium with the spokes further apart than in full-grown 
zoaria. Middle Chalk. Chatham. Vine Coll. Figd. PI. I. 
Fig. 5. 
D. 4245. A zoarium of the heaped up var. subdisciformis. Middle Chalk — 
zone of Micraster cortestudinarium. Chatham. Gamble Coll. 
Figd. PI. I. Fig. 6. 
D. 386. Two young thick zoaria (on slide). Middle Chalk — zone of Micraster 
cortestudinarium. Chatham. Gamble Coll, (identified by Gamble 
as Apsendesia organisans). 
D. 4265. A large zoarium growing on Inoceramus. Upper Chalk — zone of 
Micraster cortestudinarium. Chatham. Gamble Coll. 
D. 4259. A zoarium growing in echinid plate (on slide). ]\[iddle Chalk — zone 
of Micraster cortestudinarium. Chatham. Gamble Coll. 
D. 4075. A group of zoaria on fragment of Echinocorys scutatus, Leske 
(on slide). Middle Chalk — zone of Micraster cortestudinarium. 
Gamble Coll. 
D. 2754. A zoarium on an echinid fragment (on slide). Middle Chalk — zone of 
Micraster cortestudinarium. Chatham. G. E. Vine Coll. 
D. 2753. A large zoarium on echinid plate (on slide). Middle Chalk — zone of 
Micraster cortestudinarium. Chatham. G. E. Vine Coll. 
D. 687. A young zoarium of form Orb. (on slide). Middle Chalk — 
zone of Micraster cortestudinarium. Chatham. G. E. Vine Coll., 
Nos. 88«, 19^ ; recorded as Apsendesia papyracea^ forma organisans. 
D. 684. A zoarium attached to echinid plate (on slide). Middle Chalk — zone 
of Micraster cortestudinarium. Chatham. Vine Coll., Nos. 88, 
19^; recorded as TJnitubigera papyracea. 
