420 



Report of the State Geologist. 



PLATE LXII. 



PHYSOSPONGIA, Hall. 



Page 379. 

 (See Plates LVI, LXI ami LXIII.) 



Physospoxgia Dawsoxi, Whitfield (sp.). 



Page 381. 



Figure 1. A portion of a slender cup showing the difference in size of the 

 primary and secondary vertical bundles, the alternation of the nodes 

 and concavities and the projection of a few spicular tufts at the 

 lateral margins. 



Figure 2. A nearly entire specimen of average size, abnormal in having one 

 of the primary vertical strands of no larger size than those of the 

 secondary series. The rapid multiplication of the quadrules is 

 observable near the summit of the specimen. Some of the nodes 

 are presented in profile at the sides of the specimen. 



Figure 3. The lateral portion of an individual which shows in the matrix ihe 

 long spicular tufts extending from the intersections of the vertical 

 and horizontal bands. 



Figure 4. The median portion of a somewhat worn specimen showing the 

 alternating vertical strands, nodes and concavities. 



Figure 5. A veiy regularly developed, nearly entire cup which retains the 

 line spicular markings of the quadrules, shows the form of some of 

 the nodes in profile and two projecting spicular tufts. 



Figure 6. A specimen which has been somewhat obliquely compressed 

 shows the broad vertical primary spicular bands and the profile of 

 the nodes and spicular tufts. 



Figure 7. A larger example, showing an unusual development of the nodes, 

 and the rapid increase of nodes and concavities toward the aperture, 

 by horizontal division. 



Figure 8. An enlargement of the lateral portion of a frond showing the 

 spicular tufts arising at the intersection of the vertical and horizon- 

 tal bundles. The specimen also shows, as a discoloration of the matrix, 

 an erect lamellar film connecting the spicular tufts. This has not 

 been observed on other examples. x3. 



