ON RECENT POLYZOA. 559 
50. Retepora tubulata, Busk, ‘Chal. Rep. pl. xxviii. fig. 2, woodcut, 
p. 122, fig. 32. 
51. * columnifera, Busk, ‘Chal. Rep.’ pl. xxvi. fig. 5, wood- 
cut, p. 122, fig. 33. 
52. ” Philippinensis, Busk, ‘Chal. Rep.’ pl. xxvii. fig. 5. 
pe. i, Pheenicea, Busk, ‘Chal. Rep.’ p. 124, woodcut, and 
‘Brit. Mus. Cat.’ 
§§ 4. Owcia inconspicuous or unknown. 
54, Retepora delicatula, Busk, ‘Chal. Rep.’ pl. xxvi. fig. 3, woodcut, 
fig. 35, p. 124. 
55. - margaritacea, Busk, ‘Chal. Rep.’ pl. xxvii. fig. 2, wood- 
cut, p. 125. 
56. s Jacksoniensis, Busk, ‘Chal. Rep.’ pl. xxvii. fig. 4, 
woodcut, p. 125, 
57. »: Magellensis, Busk, ‘Chal. Rep.’ pl. xxxvi. fig. 20. 
Under the fenestrate section of the Reteporide Mr. Busk (‘ Challenger 
Report,’ p. 104, note) says that Macgillivray’s species, PrrraLia UNDATA, 
may be included in a sub-genus. I have a specimen of Macgillivray’s 
Species from Port Phillip Heads, but I have not Macgillivray’s descrip- 
tion. It isa very peculiar fenestrated form, with cells on one side only, 
and if it be included among the Rermporipa, it must be on account of 
its ‘ foliaceous and unilaminar character.’ The cells and also the ovicells 
have a very distinctive feature. 
Sub-genus 58. Reteporella, Busk. 
‘Characters those of Retepora, but the branches free in one plane.’ 
Chal. Rep. p. 126. 
This appears to me to be rather an important separation, because 
there are many fossil species of Retepora which are neither fenestrate nor 
reticulate, but which have all the characters of ordinary species. These 
may now be placed in this sub-genus, to the great advantage of the student 
of fossil forms. 
1. Reteporella flabellata, Busk, ‘Chal. Rep.’ pl. xxv. fig. 5, woodcut, 
p. 126, fig. 38. 
2. = myriozoides, Busk, ‘Chal. Rep.’ pl. xxiv. fig. 2. 
Genus 59. Turritigera, Busk. 
*‘Zoarium ramose, arising from a calcareous expansion, incrusting 
foreign bodies, having the openings of the zocecia usually on one side 
only. Zocecia ventricose or flask-shaped, much produced and sub-tubular 
above, with several conical or columnar avicularian processes on the 
-peristome.’— Chal. Rep. p. 129. 
Turritigera stellata, Busk, ‘Chal. Rep.’ pl. xxiv. fig. 1. 
“Mr. Busk very truly remarks that this ‘form appears to be more 
nearly allied to Retepora than to any other generic group, but the ver 
curious conformation of the oral portion and aperture, and its other 
peculiarities, seem to justify its being considered as generically distinct.’ 
One can hardly help speaking of the very admirable way in which 
Mr. Busk has dealt with this remarkable group. His descriptions and 
