l6o BULLETIN OF THE LABORATORIES 
longitudinal series, about eight in a length of 2 mm ; ten or eleven of 
these series are found in a width of 2 mm. The longitudinal series 
are well defined by thin, slender, raised lamellae, without the complex 
structure mentioned in the former species. The lamellae separating 
the cells from the interstitial cells appear at the surface like fine threads, 
connecting the longitudinal lamellae, and they cross each other at equal 
distances between the same, thus enclosing two interstitial cells at the 
ends of the cells. In the tubercles they become more numerous and 
either surround the cells or entirely supplant the same. The branches 
are quite thin and flat; the edges are thin and sharp, and are occupied 
by minute pores or cells, corresponding in size to the interstitial cells 
and forming only a narrow margin. Interstitial pores are apt to be 
numerous in the cell rows along the edges of the branches. Speci- 
mens usually divided at the centre, showing the epithecal laminte; 
these are wrinkled transversely, the wrinkles being lunate in the mid- 
dle of the frond, and deflected backwards on either side to the margin. 
The exterior surface is rarely seen. 
Fronds vary in size, a well grown specimen being no mm. long 
and 80 mm. broad; the branches vary between 5 and 8 mm. in width, 
and a form found at Fauver’s Quarry occasionally attains a width of 
10 mm ddieir thickness varies between 1.5 and 2 mm. 
Locality and position. Soldiers’ Home, Brown’s Quarry (a narrow 
variety), and Fauver’s Quarry, Clinton Group. 
VIII. Ph^nopora multifida, ( Van Cleve) Hall. 
{Plate XVI, Fig. 3.) 
Ptilodictya (sp ?) James, 1878, Paleontologist, No. i. (Name, P. JVelskz sng- 
gested. 
Stictopora multifida, (Van Cleve) Hall, 1883, 12th Indiana Geol. Report. 
Frond beginning with a narrow stipe, gradually widening until a 
breadth of 4 or 5 mm. is attained, then branching dichotomously at 
small angles, the branches remaining parallel. The branches may lie 
closely together and almost touch one another. They are rarely more 
than their width apart. The usual form is that of a series of parallel 
branches forming a sub-triangular frond by means of dichotomous di- 
vision, the branches at their tip being a fifth or a sixth of their breadth 
apart, and at the base touching one another, sometimes forming a con- 
tinuous frond near the stipe, and at other times being open like the 
