86 Mr. A. W. Waters on 
Mamillopora simplex (Koschinsky). 
Stichoporina simplex, Koschinsky, “Bry. der alt. Tert. des Stid- 
Bayerns,” Paleontographica, vol. xxxii. p. 64, pl. vi. figs. 4-7 (1885) ; 
Kirkpatrick, “ Flyd.& Poly. Torres Straits,” Proes Roy. ipl 
Soe. vol. vi. p. 623, pl. xvii. figs. 4 a, 6, ¢, d (1890) ; W aters, “ North 
Ital. Bry.,” Quart. "Journ. Geol. Soe. vol. xlvii. p- 3l, = iv. figs. 16-18 
ara de Angelis d’Ossat, ed- A. Neviani, ‘ Corall. e Bri. Neog. di 
Sardeana,’ ’ Bull. Soe. Geol, Ital. vol. xv. p. 16 (1897). 
Manillopora smittt, Calvet, Exp. Se. du Trav. et du Talisman, Bry. 
vol, vill. p. 424, pl. xxvil. figs. 4, 5 (1907). 
There are four species called Stichoporina in the North 
Italian Tertiary Beds, differing principally in the position 
and character of the avicularia. In S. simplex, K., there is 
on one side above the oral aperture a large triangular 
avicularium, though very occasionally one on both sides. 
Koschinsky thought that the avicularium was below the 
oral aperture, though his figure would suggest its being 
above, apparently he mistook the zowcium to which it 
belonged. The second species, S. protecta, Kosch., has, as 
described by Kosehinsky, a small round avicularium («knopf- 
formiges—mit rundlicher Offnung) at each side. This 
small ‘avicularium, according to Canu *, may be pointed. 
The third species (Cupularia) bidentata, Rss., has a small 
round avicularium at the distal end of the zocecium, and the 
ovicell is very wide, wider than figured by Reuss. Canu 
also considers that what I determined as S. semplex, Kosch., 
is the S. protecta, K., but he seems to have overlooked the 
fact that Koschinsky mentioned and figured a large triangular 
avicularium at the side of the oral aperture in S. simplex. 
S. crassilabris, Kosch, from near Lonigo, Vicentine, has a 
projection above the oral aperture, often with a large central 
process or two lateral ones. 
In neither of the four species mentioned have I seen a 
central pit, nor is one mentioned, while in (Séchoporina) 
reussi, Stol., which is the type, there is a distinct one, as 
figured by Stoliezka, and it is very marked in a specimen 
from Latdorf sent by Pergens. Other differences are 
mentioned on page 82. 
The oral aperture of S. rewsst is much smaller (about 
0°08 mm.) than that of the MW. bedentata group, in which in 
the wider part the oral aperture, contracted at the side by a 
denticle, is about 0°12 mm. It is thus seen that the group 
just mentioned does not correspond with S. reuss? and must 
be placed under Mamillopora, Smitt. Whether S. reussi 
should be placed with Batopora we may leave open. 
* Bry. Terr. Tert. des Env. de Paris, p. 101 (1907). 
