BRYOZOA. 195 
Helopora.] 
HELOPORA HARRISI James. 
PLATE III. FIGS, 11, b, c, and 12. “ 
Helopora harrisi JAMES, 1883. ‘The Paleontologist,” p. 58. 
Segments very small, acerate, about 3.5 mm. long, 0.22 mm. thick, hexagonal in 
cross-section ; upper extremity slightly expanded, conical or pyramidal, with the 
angles prominent, the lower end striated, tapering, obtusely pointed or slightly 
bulbous ; between the ends the sides are nearly parallel. Zocecia in six longitudinal 
ranges, their apertures small, narrow-elliptical, often drawn out anteriorly, their 
margins thickened, about twice their length apart, with seven (usually) on each of 
the six faces. Peristomes connected lengthwise, their sides being co-incident or 
merged into the moderately developed ridges forming the angles of the segment. 
The later are nearly always straight. Interspaces between the ends of the zocecial 
apertures occupied by a low rounded ridge, rising and spreading at each end into 
the peristomes. The best preserved examples exhibit a row of exceedingly minute 
papille on the peristomes and angle-ridges. 
In transverse sections the zocecia appear as six subequal wedge-shaped cells, 
arranged around the central axis. The outer investment is rather thin, but in most 
cases the projecting angles and the intermediate ridges are distinguishable. In 
vertical sections the anterior side of the zocecia is nearly straight, forming an angle 
of about fifty degrees with the axis. The zowcia are comparatively elongate, but the 
overlap is unusually little. Sections on the whole are much like those of Nematopora 
lineata Ulrich, as figured in Vol. viii, Ill. Geol. Sur., pl. X XIX, fig. 7, but the zocecia 
are more elongate in H. harrisi. 
I cannot doubt that this is the species named by Mr. James in the publication 
cited above, since the greater part of my specimens are from the same spot and 
layer that furnished his types. But for this certainly I would not be able to identify 
the species, Mr. James’ description being very incomplete and incorrect in some of 
the points mentioned by him. I succeeded in obtaining free from the matrix fully 
one thousand segments, and as many of these as have been examined show clearly 
and uniformily six rows of cells, not two, three, or four as he supposed. He states 
also that the sides are constricted at the ends of the apertures, “giving them a chain- 
like appearance.” This is most certainly not true of any specimen seen by me. His 
figures of the species too are as little or even less trustworthy. Indeed the two plates 
which accompany that number of “The Paleontologist” may be said to burlesque 
art illustration.* 
*Tt is really a fair question whether a species so illy and insufficiently characterlzed as this, has any claim to 
recognition. In this case it happened that I had selected the same specific name for it, we having both intended to honor 
Mr. L. H. Harris, of Waynesville, Ohio, who sent each of us one of the original specimens. 
