196 
EETECA.VA. 
the series of peristomes, whereby it agrees with R. carinata^ wliieli is 
probably its nearest ally. In that ‘ species,’ however, the peristomes 
open on a triangular ridge, which is smaller in proporiion to the 
reverse axis than in R. lichenoides. The distal ends of the branches 
of the latter have a definite median zoarial or ‘ germinal ’ layer. 
LIST OF SPECDIENS. 
D. 3548. 
D. 3643. 
D. 3502. 
D. 3542. 
D. 3220. 
D. 3540. 
D. 3228. 
D. 3742. 
D. 3221. 
D. 3235. 
D. 7069. 
D. 3231. 
D. 3225. 
D. 3226. 
D. 3236. 
Fragment of zoarium near the base (on slide). ^laastrichter 
Kreide. Maastricht. Van Breda Coll. 
Distal fragment (on slide). Maastrichter Kreide. Maastricht. 
Van Breda Coll. 
"NVorn base of a zoarium (on slide). Maastrichter Kreide. Maas- 
tricht. Van Breda Coll. 
Thin distal branch (on slide). Maastrichter Kreide. ^laastricht. 
Van Breda Coll. 
Two zoaria, showing obverse and reverse aspects. Maastrichter 
Kreide. Maastricht. Van Breda Coll. 
A thin branched fragment, with thin, flat reverse axis. Maastrichter 
Kreide. Maastricht. Van Breda Coll. 
Two fragments (in tube). Maastrichter Kreide. Maastricht. Van 
Breda Coll. 
Two fragments (on slide). Maastrichter Kreide. Petit Lana ye. 
Gamble Coll. 
Cup-shaped base of a massive zoarium ; the branches are 4 mm. 
thick. Maastrichter Kreide. Maastricht. Van Breda Coll. 
Three broken zoaria (in tube). Maastrichter Kreide. Maastricht. 
Van Breda Coll. 
A longitudinal section across a branch of D. 323o. Maastrichter 
Kreide. Maastricht. Van Breda Coll. Figd. Xo. 16, p. 195. 
A nearly complete, much branched zoarium. Maastrichter Kreide. 
Maastricht. Van Breda Coll. 
Two worn basal parts of zoaria. Maastrichter Kreide. Maastricht. 
Van Breda Coll. 
A large series of zoaria. Maastrichter Kreide. Maastricht. Van 
Breda Coll. 
A worn, basal fragment of a large zoarium, without any trace of 
Idmoniiform apertures. Maastrichter Kreide. ^Maastricht. Van 
Breda Coll. 
D. 6426, D. 6427, D. 6428. Ten specimens (on three slides). Maastrichter 
Kreide. St. Pierre and Maastricht. Busk Coll. 
