ON RECENT POLYZOA. 535 
} § a. Simplices (no marginal spines). 
1. Membranipora albida (?), Hincks, pl. xv. fig. 4. 
2M. albida, Hincks. (See following No. 33.) 
2. is crassimarginata, Hincks. (No. 30.) 
Var. a, erecta, Busk, ‘Chal. Rep.’ pl. xiv. fig. 3. 
» /, incrustaris, Busk, ‘Chai. Rep.’ pl. xv., fig. 5. 
= ? Biflustra Lacroixii, Smitt, ‘Florid Bryozoa,’ 
pl. ii. p. iv. figs. 85-88. 
§ 6. Spinosee. 
3. Membranipora spinosa, D’Orb. ‘ Voy. en Amér. Mérid.’ pl. viii. fig. 1 
= M. ciliata, Macgil. ‘Nat. Hist. Vict.’ Decade III. 
; = M. spinosa, Busk, ‘ Chal. Rep.’ p. 64. 
4. i galeata, Busk,‘ Chal. Rep.’ 64; and ‘Brit. Mus. Cat.’ 
Var. a, furcata, Busk, ‘ Chal. Rep.’ p. 64. 
» P, wmultifida, Busk, 45 :, 
» Y, erecta, Busk, i p. 65. 
Genus 33. Amphiblestrum, Gray. 
Type of Genus, Membranipora Flemingit. 
(See following list, No. 21 to 26.) 
‘A partial internal calcareous lamina. Aperture more or less trifoliate 
or obovate.’ —Chal. Rep. p. 65. 
1. Amphiblestrum imbricatum, Busk, ‘ Chal. Rep.’ pl. xv. fig. 3. 
2. + cristatum, Busk, ‘Chal. Rep.’ pl. xv. fig. 1. 
3. of papillatum, Busk, ‘ Chal. Rep.’ pl. xxxiii. fig. 1. 
4. js cervicorne, Busk, ‘Chal. Rep.’ p. 66 
= Membranipora, id. ‘ Brit. Mus. Cat.’ p. 60. 
5. r umbonatum, Busk, ‘ Chal. Rep.’ p. 66 
= Membranipora, id. ‘ Brit. Mus. Cat.’ p. 57. 
6. 43 capense, Busk, ‘Chal. Rep.’ pl. xxiii. fig. 3. 
This last species is very doubtfully placed with Amphiblestrum. 
Genus 34. Biflustra, D’ Orbigny 
= Biflustra, D’Orb.; Busk, ‘Crag Polyzoa,’ p. 71. Manzoni, 
Stolickza, Macgil. (sp.), Smitt (pars) 
= Flustrellaria (pars), D’ Orb. 
Zoarium dimorphous, encrusting or decurrent, and unilaminar, or 
foliaceous erect, and bilaminar, readily fissile in all directions. Zocecia 
in alternate series, longitudinal or transverse. Zocecia flustrine, quad- 
rangular or hexagonal (?), with a denticulate lamina at bottom. 
Biflustra Savartii, Awdouin, ‘ Chal. Rep.’ pl. xiv. fig. 2 
= Flustra, id. Aud., ‘ Mgypte’ pl. x. fig. 10 
= Membranipora, id. D’Orb., ‘ Paleon.’; Busk, ‘ Crag Polyzoa,’ 
: p- ol. 
= A corrugata, Blainv. 
= Biflustra Savartii, Smt, ‘ Florid. Bry.’ 
_ Mr. Busk says of this species that there may be some doubt whether 
this is really Flustra Savartii of Savigny and of the Crag. 
