480 PALEONTOLOGY OF ILLINOIS. 



FISTULIPORA SPINULIFERA Rominger. 



PL XLVI, Fig. 3-3d. 

 Fistuhpora spinulifera Bominger, 1866. Proc. Acad. Nat. Sci. Phila., p. 121. 



Zoarium ramose, branches one to three cm. in diameter. Sur- 

 face monticulose; the small, prominent, conical, and sub-solid 

 monticules about three mm. apart, and arranged in rows of 

 considerable regularity. Monticules composed of vesicular tissue 

 and, like the interzooecial spaces, minutely spinous when in a 

 good state of preservation. Apertures sub-oval, about 0.20 mm. 

 in their greatest width, and between six and seven in two mm. 

 Lunarium but little elevated, the ends sometimes prominent and 

 projecting slightly into the zocecial cavity. Zocecial tubes thin 

 walled, proceeding in a gradual curve to the surface upon which 

 they open almost perpendicularly. Diaphragms rather irregular 

 in position and distribution, none in the central part, few in the 

 outer portion of the axial region, numerous in the cortical re- 

 gion. Vesicles irregular, usually small, angular, very large in 

 the axial region, becoming gradually much shallower toward 

 the surface, surrounding the zocecia in one or two series. In 

 tangential sections the lunarium shows but faintly. These sec- 

 tions also show a large number of small spots, that resemble 

 thin-walled acanthopores. They do not appear to form con- 

 tinuous tubuli. 



This form closely resembles monticulated specimens of an asso- 

 ciated species of Monotrypella, from which it should be dis- 

 criminated. An examination with the hand lens readily does 

 this. The ramose habit of growth, solid branches, and com- 

 paratively thin granulose interspaces, distinguish it from other 

 species of the genus. 



Position and locality: Hamilton group, Alpena, Mich. 



FlSTULIPOKA (?DlCHOTRYPA) CORRUGATA UMch. 

 PL XL VII, Fig. 8-8a, and PI. XL VIII, Fig. 6-6b. 



Zoarium an irregular undulating or somewhat distorted ex- 

 pansion, one mm. or there about in thickness. Under surface 

 with a concentrically wrinkled epitheca, the wrinkles strong, sub- 

 equal, and closely approximated. Sharply denned, small solid 

 maculae, of stellate form, dot the celluliferous surface and are but 



