430 PALEONTOLOGY OF ILLINOIS. 



LEIOCLEMA PUNCTATUM Hall. 



Callopora punctata Hall. 1868. Geol. Iowa, Vol. I, part II. Pal. p. 653. 

 Callopora missouriensis Kominger, 1866. Proe. Aead. Nat. Sci. Phila. p. 117. 

 Leioclema punctata Ulrich, 1882. Jour. Cin. Soc. Nat. Hist. Vol. V. p. 141. 

 PL VI, fig. 1, la. 



Zoarium ramose, reaching a height sometimes of fifteen to 

 twenty cm., branches from two to five, generally about four 

 mm. in diameter, springing from a broad irregular basal ex- 

 pansion, which may be free and with a wrinkled basal epitheca 

 or attached to foreign bodies. Surface smooth or slightly 

 tubercled, in well preserved specimens, spinulose, having a hir- 

 sute appearance under a pocket lens. Walls of zooecia flexuous 

 in the axial region, comparatively thick in the peripheral region. 

 Zooecia about five or six in the space of two mm., with sub-cir- 

 cular, or petaloid apertures, from 0.15 to 0.2 mm. in diameter. 

 Mesopores sub-angular, small, their diameter about one-third 

 that of the zooecia, arranged in two or three or more series 

 about the zooecia, frequently aggregated into large irregular 

 groups, comparatively more numerous on the basal portion 

 than higher up on the zoarium. Diaphragms strong, few and 

 remote in the zocecial tubes, more numerous and about their 

 own diameter apart in the mesopores. Acanthopores large and 

 numerous, from four to seven encircling the zooecia and en- 

 croaching upon their visceral cavity, causing the floriform ap- 

 pearance of the zooecia observed in tangential sections and 

 upon the surface. 



The robust habit of growth distinguishes this species from L. 

 gracillimum. The great abundance of mesopores and acantho- 

 pores, in connection with the growth, separates it from all other 

 species of the genus. 



Position and locality: This is the most abundant species in 

 the Keokuk limestone, occurring at Keokuk and other localities 

 in Iowa; Warsaw 111.; Lagrange, Mo. (Rominger); and King's 

 Mountain, Ky. Also in the Warsaw beds. 



