11 
relationship will be indicated, but how far general classifi- 
cation may be assisted must remain open until larger series 
have been examined. 
EXPLANATION OF PLATE. 
Opercula of 
1 Lepralia Cecilii, Aud. 
2 ■ vulgaris, Moll. 
3 pertusa, var. 
4 — — , var. 
5 Cellepora. 
6 Lepralia arrogata, Waters. 
7 linearis, Hass, var typica SmitJ. 
8 Cellepora. 
9 Lepralia errata. 
10 Cellepora Hassallii, John. 
11 verruculata, Smitt. 
12 Cellepora. 
13 Lepralia auriculata, Hass. 
14 cucullata. Busk. 
15 Myriozoum truncatum, Pall. 
16 Lepralia. 
17 Lepralia Pallasiana, Moll, var projecta, W. 
IB coccinea, Abild. 
19 Pallasiana, Moll. 
20 lata. Busk. This is larger than most opercula of lata. 
21 Eschara contorta, Busk. 
22 Retepora Couchii, Hincks. 
23 cellulosa, Jam. 
24 Lepralia foliacea, stadium Hemeschara. 
25 Eschara foliacea, Ell & Sol. 
26 Lepralia reticulata, Macg. var ophidiana, W. 
27 Cellepora sardonica. Waters. 
28 Eschara verrucosa, Peach. 
29 Lepralia ciliata, Pall. 
30 Malusii, Aud. 
31 bimucronata, Moll. 
32 Brongniartii, Aud. 
33 rectieulata, Macg. var inequalis, Waters. 
34 G-attyae, Lands. 
35 Tubucellaria hirsuta, Busk. 
36 cereoides, Ell & Sol. (in section). 
37 Ditto do. 
All magnified 85 times. 
