2i8 The Ottawa Naturalist. [February 



transverse diaphragjms either none or rudimentary ; increase by 

 lateral budding. " 



The type specimen, by far the most perfect specimen in the 

 collection, has been closely examined and by means of a longitud- 

 inal section of one of the corallites close set complete horizontal 

 tabulae are found to be present. The supposed absence or rudi- 

 mentary condition of tabulae being the only character distin- 

 guishing PalcBopJiyllum from Columnaria, the knowledge that 

 tabulae exist removes the barrier to the union of these two genera. 



Columnaria rugosa may be defined as follows, — corallum 

 consisting of an aggregation of circular or rounded polygonal 

 corallites, from about 3 to 9 mm. in diameter, which are in con- 

 tact with one another or free for greater or less distances. Septa, 

 numbering about forty in well developed corallites, alternately 

 long and short, the long ones reaching to or almost to the centre, 

 the short ones almost rudimentary. Tabulae complete, horizon- 

 tal, slightly irregular, at times slightly concave or convex and 

 often turned downward at their edges, about four in the space 

 of 2 mm. Increase by lateral calicular gemmation. Exterior 

 of corallites marked by annular lines of growth and faint longi- 

 tudinal lines corresponding with the septa within. 



The corallites in this species vary considerably in size in 

 some specimens, in others they are more uniform and when in 

 contact whether circular or polygonal they still remain distinct 

 one from another generally with interspaces between them. 



Coluvinaria erratica, Billings was described as "forming 

 large masses of corallites, either in contact or separate. The 

 separate cells are round, those in contact more or less polygonal, 

 the radiating septa rudimentary, forming about four sulci in the 

 breadth of one line upon the interior ; diameter of corallites 

 from two to five lines, in general about three and a-half lines. 

 The transverse diaphragms are not visible in the specimens ex- 

 amined. The walls of the separate corallites are thick and con- 

 cen:rically wrinkled." This species is now represented in the 

 museum collection by a single specimen labelled in the hand- 

 writing of Mr. Billings and consists of a corallum with corallites 



