192 DEVONIAN FAUNA. 



Localities. — There is a specimen from Croyde Bay in my Collection, and three 

 slabs containing several specimens from Top Orchard in the Woodwardian 

 Museum. 



Remarks. — This little species seems rare, but from its slightness it may easily 

 have been overlooked. It is very different from P. bipinnata, and I am not aware 

 of any species which it at all resembles. The very large and variable number of 

 cells between adjacent branches, the acuteness of the angle at which the branches 

 are set, the repetition of branching in the lateral branches, and the greatness of 

 the width of the intervals compared with the width of the branches, as well as 

 possibly the shape of the cells, appear to be distinguishing features. 



The pieces I have seen are very small, but it is possible that they are only 

 fragments from larger specimens. 



III. Family — STREBLOTRYPiDiE, TJlrich, 1890. 



"Zoaria variable. Zocecia with primitive portion subtubular or tubular; 

 apertures subcircular, often truncated posteriorly, surrounded by a slightly 

 elevated rim. Front or outer portion of cell, back of the aperture, simply 

 depressed, or with from two to twelve or more small pits. Diaphragms wanting " 

 (Dlrich). 1 



1. Genus — Stkeblotryfa, TJlrich, 1890. 



"Zoaria ramose, slender, solid. Zooecia radiating from an imaginary axis, 

 with primitive portion long, tubular ; or from a linear axis, when they are somewhat 

 shorter. . . . Apertures regularly elliptic or truncated at the posterior margin, 

 surrounded by a slight peristome, and within this sometimes a narrow sloping 

 area; arranged usually in rather regular longitudinal series. Just back of the 

 aperture, occupying the depressed front of the cell, are from one to twelve small 

 pits, which, when numerous, are arranged in two or three rows. Very small 

 acanthopores occasionally present" (Ulrich, 2 abbreviated). 



1 . Streblotrypa Gregorii, Whidbome. Plate XXIII, figs. 10, 10 a. 



1896. Steebloteypa Gregobii, Whidbome. Proc. Geol. Assoc, vol. xiv, p. 376. 



Description. — Zoarium cylindrical, small, with strong, acute, elevated, undu- 

 lating, longitudinal ridges dividing the cell-areas. Areas elongate, irregularly 



1 1890, Ulrich, ' Geol. Surv. Illin.,' vol. viii, p. -402. 



2 Ibid., p. 403. 



