CELLULARINE AND OTHER POLYZOA. 295 
"introdaction. The consideration of a number of genera at the same time hag 
had great advantages, by enabling many cases to be discovered in which the 
conclusions drawn from the study of one genus by itself are modified by 
iiaking otliers into account. I have found it necessary to propose the following 
new genera and species in the present Section : — 
Camptojolites, n. gen. 
Didi/mozoum, nom. nov., to replace Didymia, pre-occupied. 
Euoplozoum, n. gen. 
Himantozoum, n. gen. 
Onclioporella huskii, nom. nov., for Onclioporella bomln/cina, Busk. 
Stirpariella, nom. nov., to replace Stirparia, pre-occupied. 
The following new names are proposed in Sect. V. : — 
Amastigia kirkpatricki (Levinsen, MSS.), n. sp. 
Menipea vectifera, n. sp. 
Notoplites, n. gen., and N. rostratus, n. sp. 
I accept the main divisions of the Cheilostomata which were suggested by 
Levinsen (1909, pp. 88-90). The Order is divided into two Sub-Orders: 
(1) Anasca, in which the original frontal membrane persists, wholly or in 
■part, in a membranous condition ; (2) Ascophora, in which a compensation- 
sac is present [cf. Harmer, Q. J. M. S. xlvi. p. 263). The Anasca are further 
subdivided into three Divisions : (i.) Malacostega, with the frontal membrane 
for the most part in its primitive, membranous condition ; (ii.) Coilostega, 
with a considerable development of a calcareous layer, the cryptocyst, 
subjacent to the frontal membrane, and frequently pierced by foramina, the 
opesiules, ti-aversed by the tendons of the depressor muscles, which are 
inserted into the frontal membrane ; (iii.) Pseudostega, with peculiar, 
immersed ovicells and certain other characters, consisting mainly of the 
Family Cellariidas. 
The genera included in the following list are mainly the erect branching 
•forms of the Anasca. I have included all Levinsen's Families of recent 
Malacostega, with the exception of the Membraniporidse and Cribrilinidse ; 
the erect, branching genera of the Coilostega, but not the encrusting forms 
nor those with an Escharine habit; and the genera of recent Pseudostega. 
The Oellularine assemblage, with which I am principally concerned, consists of 
the branching, erect genera of the Malacostega. The branching Ascophorous 
■genera, such as the Catenicellidse, provided with a compensation-sac, are 
not included in my list, with one or two exceptions, in the case of names 
which have some bearing on the nomenclature of other genera under 
consideration. 
22* 
