NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
Genus BIMORPHOCELLA Maplestone, 1903. 
571 
1903. Dimorpliocella Maplestone, Further descriptions of the Tertiary Polyzoa of Victoria, 
Article IX, Transactions Royal Society Victoria, p. 140. 
“Two distinct forms of cells. Zooecial cells elongated or rhomboidal. distinct. 
Thyrostome [aperture] arched above, with a sinus in the lower lip. Ooecial cells 
[gonoecia] much larger than the zooecia, elongate, pyriform or oval, with a broad 
aperture and a perforated area in front.” (Maplestone.) 
Genotype. — D imorpJweella ( A.deonella ) triton MacGillivray, 1895. Miocene. 
The other known species of this genus are : 
Dimorphocella pyriforrnis Maplestone, 1903. Miocene. 
Dimorphocella portmarina Maplestone, 1903. Recent. 
C *24 
Fig. 170. — Genus Dimorpliocella Maplestone, 1903. 
A, B. Dimorphocella triton MacGillivray, 1895. A. Group of zooecia, including gonoecia. 
B. Normal zooecia. (A, B after MacGillivray, 1S95.) 
C. Dimorpliocella portmarina Maplestone, 1903. Group of zooecia, X 24. (After Maple- 
stone, 1903.) 
According to the definition and examination of the figures the ordinary zooecia 
have no ascopores, whereas the gonoecia are provided with them. On the recent 
species DimorplioceUa portmarina there are some ascopores on the two kinds of 
zooecia. F urtlier study is therefore necessary to establish the validity of this genus. 
Genus LAMINOPORA Michelin, 1842. 
1842. Laminopora Michelin, Magasin de Zoologie, pi. 3. 
The apertura is very elongate; the anter is semielliptical; the poster bears a 
long, rounded rimule; two small cardelles separate the two latter parts; the oper- 
culum bears two lateral denticles articulating on the cardelles. The frontal is a 
tremocjist with pores not stellate. The gonoecia have no special form. 13-15 
tentacles. 
Genotype. — Laminopora contorta Michelin, 1842. Recent. 
Gemellipora arbuscula Calvet, 1907, belongs to this genus. 
