202 ANNALS NEW YORK ACADEMY OF SCIENCES 



tlie\- are rare. Acanthopores are large and moderately numerous. [Nleso- 

 pores absent. 



This type belongs without much question to the Batostomellidae but 

 can not be placed in any of the groups there recognized as at present 

 defined. The mode of growth is that of Anisotrypa, but the structure is 

 otherwise different. The structure is that of some not quite typical 

 species of Stenopora (not typical because of the rarity of the diaphragms 

 and the continuous or fused thickening of the mature wall), but the 

 mode of growth is distinct from that of Stenopora. 



To some extent, the mode of growth seen in this group appears gener- 

 ally to be regarded as a generic character, and probably the present type 

 can with propriety be assigned to subgeneric rank on that account. 



Type. — Cceloclemis tumida. 



Cceloclemis tumida sp. nov. 



Zoariuru consisting of hollow stems lined with an epitheca : irregularly 

 branched and with swollen portions, monticules (?), etc. Cross sections gen- 

 erally circular, just preceding bifurcation, compressed. The largest diameter 

 observed is 9 mm., but the average is about 5 mm., while the smallest noted 

 is 3 mm. The thickness of the wall, that is the thickness of the zoarium, is 

 from .5 to 1 mm. or more. 



The zocecia appear to have a rather long, prostrate portion from which they 

 hend outward strongly to a radial direction. The presence of tabulie has not 

 been definitely determined. If developed at all. they appear to be rare and 

 restricted to the prostrate portion. Thp walls are as usual thin in the imma- 

 ture zone. At the surface, they vary, certain areas being thin- and others 

 thick-walled. The thick-walled areas are sometimes, though not always, 

 associated with prominences (monticules). The zooecia vary in size, there 

 being occasional gi'oups of large cells, though there are considerable areas 

 upon which the cells appear to be undifferentiated in that way. The aper- 

 tures are angular, with rounded corners where the walls are thick. Five or 

 occur in 2 mm. Acanthopores are fairly abundant, situated at the angles 

 where develoiied. but not all the angles are filled. Where the walls are thin, 

 the acanthopores indent the cells : otherwise they are imbedded in the walls 

 without deforming the zooecia. In addition to the large acanthopores. the 

 wnlls where thickened have many small spinules distributed through them. 

 Though especially abundant there, these are not restricted to the median line, 

 which is well defined by a continuoiis dark band. The median line is also 

 shown when the walls are quite thin. When cut lengthwise, the walls are 

 thin in the immature and usually much thickened in the mature region. This 

 thickening begins abruptly and is continuous. 



Pycnopora subgen. nov. 



This name is introduced in a subgeneric sense for a bryozoan type 

 whose affinities are clearly close with Lioclema. The t^^pe species grows 



