CONSTELLARIIDiE. 39 
NlCIIOLSONELLA RINGUEBERGI n. Sp. 
PI. XIV, figs. 12, 13. 
The various collections from the Rochester shale have shown half a dozen specimens of 
a species of Nicholsonetta agreeing with the associated N. florida in method of growth but 
differing decidedly in the size of the zooecia and in several internal characters. This form, 
for which the name •Nicholsonetta ringuebergi is proposed, has seven zocecia in 2 mm., a fea- 
ture in marked contrast with N. florida, which has two to three in the same space. 
The average zooecium of N .florida is 0.50 mm. in diameter, while that of N . ringuebergi is 
only 0.23 mm. Internally the absence of diaphragms in the zooecial tubes will further 
distinguish the present species from the associated form. 
This neat species is named in honor of Dr. E. N. S. Ringueberg, of Lockport, N. Y., in 
appreciation of his work on the paleontology of the Rochester shale. The small, floriform 
apertures, many acanthopores, and the explanate growth will readily distinguish this from 
other bryozoa of this region. 
Occurrence. — Rather uncommon at Lockport, N. Y. 
Catalogue number, 35493, U. S. National Museum. 
( ionus IDIOTRYPA Ulrich. 
Idiotrypa Ulrich, Jour. Cincinnati Soc. Nat. Hist., VI, 1883, p. 272. 
Idiotrypa Miller, North American Geol. and Pal., 1889, p. 310. 
Idiotrypa Ulrich, Gcol. Survey Illinois, VIII, 1890, p. '375. 
Idiotrypa Simpson, Fourteenth Ann. Rept. State Geol. New York for 1894, 1897, p. 591. 
This genus was established by Ulrich for the reception of a single species, 7. parasitica, 
from the Osgood beds of the Niagaran of Indiana. The genus was supposed to differ 
fundamentally from all trepostomatous genera in that the zoarium was not clearly differ- 
entiated into mature and immature regions. Further, the development of the tabula' at 
equal distances from each other in both zocecia and mesopores seemed so much at variance 
with that obtaining in the monticuliporoids as then known that the systematic position of 
the genus appeared more doubtful. The peculiar tabulation Ulrich held to be essentially 
comparable with that characterizing Cumulipora, a Cretaceous genus of the Chilostomata, 
which agrees further with Idiotrypa in having similarly perforated diaphragms. Subse- 
quently this author recognized the true affinities of the genus by allying it with Constellaria 
and Nicholsonetta. a 
Idiotrypa parasitica occurs rarely at the Indiana locality, but a number of specimens 
identical with Ulrich 's species have been found at Lockport and other New York localities. 
The sections figured by Ulrich were prepared from a mature example in which the peculiar 
tabulation and pores are developed to the utmost. These sections also happened not to 
show an immature region. On Pis. XVII and XXIV Ulrich's figures and also other views 
of the internal characters of the species are reproduced, and the latter especially show 
that the genus is a true member of the Trepostomata, differing decidedly from other genera 
of this suborder onty in development of diaphragm in both zocecia and mesopores at 
frequent and equal distances. The structure of the zocecia and mesopores otherwise is 
precisely like that characterizing the Constellariidse several species of Nicholsonetta espe- 
cially showing very similar pores or foramina penetrating the walls and mesopores. Indeed, 
the genus is so near Nicholsonetta that the only important difference seems to be the equal 
development of diaphragms in both zooecia and mesopores. 
a Geol. Survey Illinois, VIII, 1890, p. 375. 
