BRYOZOA. 133 
Rhinidictya.] 
manner causing the transverse interspaces to appear as bearing three longitudinal 
strie or rows of granules. Margin of branches acute, the non-celluliferous band 
rather wide and occupied by one or more lines of papille. 
Of internal characters it will suffice to mention that there is a well-developed 
superior hemiseptum, and a greater number of median tubuli in the end spaces 
between the zocecial apertures (see fig. 18) than in any other species known to me. 
This pretty little species is not likely to be confounded with any of the preced- 
ing, unless it be with R. exigua, But the surface characters, especially when well 
preserved, are so very dissimilar that confusion, even in that case, is inexcusable. 
Var. MODESTA 2. var. 
PLATE V, FIG. 17. 
4 . 
Under this subordinate name I propose provisionally to classify an associated 
form, differing in some respects constantly from the typical variety. Both are rep- 
resented “by numerous specimens, with no question in any case as to where each 
belongs. They agree, however, too closely in the more important elements of struc- 
ture to admit of specific separation. Except in the case of subsequent discoveries in 
other regions proving the supposed new variety to hold its own geographically, the 
above degree of separation seems to me sufficient. My studies of the paleozoic bifo- 
liate Bryozoa have taught me to distrust mere deviations in the width of the branches 
as being good specific characters. ‘ : 
In the variety the branches are wider, the width varying from 1.7 mm to 3.0 mm., 
the zocecial apertures larger, and the interspaces correspondingly narrower. Still, the 
number of apertures in 5 mm., measuring lengthwise, is, as in the typical form, about 
sixteen. In the best preserved specimens the superficial characters resemble those 
of young examples of typical minima very closely, the chief difference being that the 
zocecial apertures, as already stated, are larger, and the non-poriferous band gener- 
ally wider and grano-striated obliquely instead of longitudinally. The striz also 
project slightly beyond the edge. causing the latter to be minutely serrate. 
When the drawings for this species were prepared I possessed, unfortunately, 
only a few specimens. The number was subsequently greatly increased by pickings 
from washings of shales from the original locality, kindly sent me by Mr. W. H. 
Scofield, of Cannon Falls. 
Formation and locatity.—Galena shales, near Cannon Falls, Minnesota; associated with species of 
Nematopora, Arthropora armatum, Diastoporina flabellata, and other small Bryozoa characterizing the 
horizon, td 
Mus. Reg. No. 8105. Var. modesta, 8106. 
