Bryozoa of the Hamilton Group. 63 



shows that the frond could not have been continuous ; the largest frag- 

 ment observed is three and one-half centimetres long and two and one- 

 half wide. 



Branches comparatively strong, increasing in size but slightly, if any, 

 below bifurcations; width of branch .66 mm.; branches flexuous, 

 regularly bent from side to side, forming on each side of the branch 

 convexities and concavities, which alternate with each other, the con- 

 vexities of contiguous branches uniting and coalescing; on non-porif- 

 erous side the branches are slightly angular, with a carina running 

 along the middle ; the carinas of two contiguous branches, at the 

 anastomosed part, sometimes unite and form on that portion one car- 

 ina, at other times there is a space of .25 mm. or more, which is deeply 

 channeled. 



Dissepiments or anastomosed portions of the branch vary in width 

 from .66 mm. to 1.33 mm.; the narrower ones are in reality not anas- 

 tomosing, but very short celluliferous dissepiments ; there are three in 

 the space of five millimetres. 



Fenestrules oval, one millimetre in length, .66 mm. in width. 



Cells in three ranges ; on the dissepiments sometimes one or two 

 ranges more ; apertures minute, circular, a little more than .20 mm. 

 in diameter, closely arranged, frequently nearly contiguous, eighteen in 

 the space of five millimetres; the central range opens directly upward, 

 the outer range nearly directly upward, very slightly laterally ; mar- 

 gins comparatively strong, very distinctly elevated. 



Formation and locality. Hamilton group ; Ontario, Canada. 



Fekestella perundulata, n. sp. 



Bryozoan probably infundibuliform in shape. 



Branches moderately strong, .5 mm. in width ; space between the 

 branches more than the width of the branches, seven branches in the 

 space of five millimetres ; on non-poriferous side angular, carinated ; 

 carina and upper part of the branch regularly flexuous ; at the dissepi- 

 ments the carina and angular portion of the branches frequently meet 

 and coalesce, giving the appearance of anastomosing branches. 



Dissepiments strong, from .50 to .66 mm. in width, expanding at 

 their junction with the branches, about three in the space of five mil- 

 limetres ; on non-poriferous side, angular and on a plane with the 

 branches; on poriferous side depressed, rounding. 



Fenestrules small, oval, .75 mm. in length, .5 mm. in width. 



Cells in two ranges ; apertures small, circular, opening nearly directly 

 upward, about .16 mm. in diameter, distance apart less than the diam- 

 eter of an aperture, about twenty in the space of five millimetres ; 

 margins distinctly elevated ; space between ranges of apertures cari- 

 nated ; carina strong, with an elevation equal to the thickness of a 

 branch, and slightly expanded and flattened at the top ; width of 

 expanded portion .25 mm. ; finely striated. 



On the poriferous face the branches, carinations and ranges of aper- 

 tures are straight, presenting a somewhat rigid appearance, while on 

 the non-poriferous face the whole upper portion of the branch is regu- 



