58 Thirty-sixth Keport on the State Museum. 



space of three millimetres, and for the remaining two millimetres 

 four ranges of cell apertures. Cells minute, circular, about .12 mm. in 

 diameter, distant from each other equal to the diameter of an aperture, 

 twenty in the space of one millimetre, four in the space of one fenes- 

 trule, counting those opposite the dissepiment ; margins distinctly ele- 

 vated, and those of the outer rows indenting the border of the fenestrule; 

 apertures sometimes alternating and forming oblique transverse rows, 

 at other times irregularly arranged ; where two rows occur the aper- 

 tures open directly upward ; where three or four rows occur the central 

 row or rows open directly upward, and the two outer rows laterally ; 

 space between rows of apertures smooth. 



Formation and localities. Hamilton group; Moscow, Livingston 

 county, and Alden, Erie county, N". Y. 



/ Fen"estella latitruncata, n. sp. 



Bryozoan, occurring only' in fragments ; the form of frond is not 

 certainly known, but probably is infundibuliform. 



Branches strong, gradually enlarging to the bifurcations ; width 

 just below bifurcation one and one-third millimetres, just above, two- 

 thirds to three-fourths of one millimetre; the distance between the 

 branches is from one-half to four-fifths of one millimetre ; three to four 

 branches in the space of five millimetres; on non-poriferous side the 

 branches are slightly angular. 



Dissepiments about .5 mm. in diameter, slightly expanding at their 

 junction with the branches, two in the space of five millimetres; on 

 non-poriferous side, on a plane with the branches, slightly arching and 

 angular; on poriferous side slightly depressed, rounded. 



Fenestrules, on non-poriferous side, subquadrangular ; on porifer- 

 ous side oval, in outline ; length one and three-fourths millimetres. 



Cells arranged in from three to six ranges ; cell apertures minute, 

 circular .14 mm. in diameter, distant from each other a little more 

 than the diameter of an aperture, sixteen in the space of five milli- 

 metres longitudinally; margins distinctly elevated, and those of the 

 outer rows indenting the border of the fenestrules, so much so, that 

 the margins are plainly visible from the non-poriferous side, giving a 

 somewhat serrate appearance to the margin, alternating and forming 

 oblique, transverse rows ; the longitudinal rows are separated by a fine, 

 slightly elevated carina; the space between the apertures, longitudinally, 

 has sometimes a single striation. 



Where fragments of this species occur, from the large branches, and 

 the widening below the bifurcations, which, when the branches are 

 broken off a short distance above, present a clavate appearance, they 

 very much resemble a Thamniscus, this is especially the case where 

 the depressed dissepiments of the poriferous side are covered with sedi- 

 ment, while the branches are not ; without a critical examination it 

 would be considered a Thamniscus. 



This species can be distinguished from F. multiplex by its more 

 robust form, and the greater number of ranges of cell apertures. 



Formation and locality. Hamilton group; Ontario, Canada. 



