Specos of the Keokuk Grolp. 



187 



ment3 represented in figure 35. The smaller of these probably belong to the 

 parenchymalia hut the larger has not been located. 



There is a very considerable variety in the forms which may be referred 

 to the parenchymalia and dermalia. Perhaps the most striking of these are the 

 large and small umbels (umbels and micnimbels ; figs. 34, 35, 36 and 37). These 

 are like the dermal clavules which have been figured by F, E. Sciiulze in the 

 recent species Farrea occa* except that here the shafts are always short and 

 smooth, gently swollen beneath the umbels, and the teeth of the umbels 

 smooth. They evidently have nothing to do with the anchoring spicules or 

 basalia, and the same is probably true of the anchor-shaped fragment 

 shown in fig. 37 (16) which was taken from the upper part of the cup. 

 To the dermalia may also be referred the peculiar compound tri-pinulus, 

 both sides of the complete form of which are shown in figure 37 (5, 6). 

 The morphology of this spicule is not readily apprehended. There are also 

 other peculiar pinulus forms as shown in figures 34 (2) and 37 (7, 9, 10, 11, 

 13), which are as yet incompletely known. In figure 37 (8) is an imper- 

 fect amphiaster belonging to the parenchymalia. 



Dimensions. The original specimen measures 130 mm. in height, 

 70 mm. in diameter at the base, 100 mm. across the nodose expansion, 65 mm. 

 where narrowest, and about 75 mm. at the upper end which is imperfect. 



Locality. In the calcareous shales at Crawfordsville, Indiana. 



PHYSOSPONGIA, Hall. 

 1881. UphankBma, Whitfield. American Journal of Science, vol. xxii, p. 132. 

 1881. Uphankenia, Dawson. American Journal of Science, vol. xxii, p. 132. 



1881. UpTiantcmia, Whitfield. Bull. No. 1, Amer. Mus. Nat. Hist., p. 15. 



1882. Fhyso.'ipongia, Hall. Notes on the Family Dictyospongidae ; Expl. 



pi. 19. 

 1884. Physospongia, Hall. Thirty-fifth Ann. Kept. N. Y. State Mus. Nat 

 Hist., pp. 467, 479-481. 

 The fossils of this genus have the form of a diminutive basket with broad 

 strands and coarse meshes. The upright body has a very gradual expansion 

 from the base upward and its surface was probably regular, as far as appears 

 from the usual mode of preservation, though it is possible that, when com- 

 pressed, the strong vertical strands of the spicules may have given it a some- 

 what prismatic form. Nonnally the surface bears two series of these vertical 



• Haxactlnellldae, pi Uxl, flc>. S, 9, ». 



