490 Mr. W. K. Bridgman on the Influence of the Venation 



Cytherella lunata (n. sp.), fig. 6. 



Ovato-oblong j dorsal edge slightly concave, giving the valves a 

 tendency to a semilunar figure ; valves unequal ; length 

 3^'y inch, height ~ inch. 



The very strong resemblance these Entomostraca have to the 

 subgenus proposed by Mr. T. 11. Jones in his Monograph on 

 the Cretaceous species, as well as the constant and great pecu- 

 liarity of one valve projecting beyond the other, give the author 

 no hesitation in placing it among the Cytherella. It is a much 

 smaller species than the last. 



Ceriopora rhombifera (Goldf.), figs. 7, 7 a. 



Polypidom cylindrical, jointed, dichotomous ; cells rhomboidal, 

 immersed, diverging from the axis, arranged in quincuncial 

 order, and opening on the surface ; aperture in centre of cell, 

 labiate ; cells -^^ inch long, y^^ inch broad j branches from 

 -^ inch to ^ inch in diameter. 



Poteriocrinus ? fig. 8 «, b, c, d, e,f. 



Ossicula {a, h, c) round, with a central aperture or depression, 

 striated ; striae distant about -^^-q inch ; the largest ossicula 

 about ^ inch in diam., and the smallest —^ > ^^^ central aper- 

 ture J^ inch ; the cast of the columnar cavity (fig. 8 e, /) = 

 — y inch ; perisomic plate {d) granulated, granulations ^^^ inch 

 in diameter, and distant about the -^^-q inch. 



From the almost universal dismemberment of the specimen, 

 the species has not yet been determined. It is about the size of 

 Major Austin^s P. isacobus ; and as this species occurs not far 

 from the locality, it may very likely turn out eventually to be 

 identical. Unfortunately, no measurements are given in Major 

 Austin's very beautiful monograph. 



A great many more forms abound in this remarkable deposit, 

 and may with equal facility be separated from the matrix and 

 removed in a perfect condition. 



L. — On the Influence of the Venation in the Reproduction of 

 Monstrosities among Ferns. By W. Kencely Bridgman, 

 L.D.S., Il.C.S.E. 



In the propagation of Ferns, most of the " sports," or natural 

 deviations from the typical form, may be reproduced from their 

 spores; but, in thus multiplying them, it is well known that 



