GIRTY, NEW CARBONIFEROUS FOSSILS 209 



In tangential section, the zooecia are seen to be elliptical in section, not 

 quite twice as long as wide. The intervals laterally are slightl}^ less than 

 the width of the tubes. Longitudinally, the distance is more than the 

 length of the long diameter, but occasionally less and occasionally also 

 twice as great. A large acanthopore-like spine occurs near the end of 

 each aperture, while a row of smaller ones traverses the middle of each 

 wall. The smaller spines are more superficial than the large ones, and 

 fewer of them show in proportion as the section is cut farther from the 

 surface, so that in some cases they appear to be well-nigh absent. 



Streblotrypa nickelsi var. robusta var. nov. 



Zoarium in the form of long, cylindrical stems which are sometimes more 

 or less bent and but seldom branched. Diameter a little less than 1 mm. 

 Apertures in alternating linear rows, about 12 to the circumference. They 

 are ovate, broader and more truncated on the posterior side, surrounded by a 

 distinct peristome which is confluent with the raised longitudinal lines that 

 divide the rows of apertures. The longitudinal lines are somewhat sinuous, 

 contracting downward from the base of one aperture to the top of the next. 

 Spaces between the zooecial apertures in the same row twice or more the 

 length of the apertures themselves, somewhat depi'essed, occupied by about 12 

 pores, variable in number and in size. Usually they are arranged in 2 rows, 

 5 or 6 pores in each, while the widening of the interzocecial areas toward the 

 top leaves room for an additional intermediate incomplete row of 2 or 3. 

 There are 4 apertures and 4 interzocecial areas in 2 mm. longitudinally. The 

 zocBcial tubes are long, gradually diverging, rather abruptly turning outward 

 when near the surface. Hemisepta about as in S. nickelsi. 



Coeloconus tuba sp. nov. 



Zoarium in the form of a gradually enlarging cone, more or less contorted, 

 attaining a length of at least 13 mm. and a diameter of 3.5 mm. Usually the 

 fossil appears as a mold of the interior, partly embedded in rock, the 

 zoarium itself adhering to the external rather than to the internal matrix. 

 In this condition, it appears to be marked by more or less closely arranged, 

 regular constrictions or by fine sharp annulations. In one specimen, the con- 

 strictions are much coarser and more irregular. There are also fine concen- 

 tric strise and obscure linear longitudinal markings. Some of the specimens 

 taper gradually to a point, while others contract suddenly, so that the lower 

 end appears truncated and rounded. These differences may be indicative of 

 different species, but my material is so scanty that it has seemed inexpedient 

 to sacrifice it to ascertain this fact by sectioning. 



As the specimens examined show no external characters beyond those men- 

 tioned, which are probably not truly specific in value, the essential part of the 

 description is based on thin sections. The walls of the zoarium are .28 mm. 

 in thickness. The basal plate is thin. The partitions extend obliquely up- 

 ward ; tlie ends bend somewhat inward into hook-like hemisepta, while the 

 outer surface is abruptly and strongly thickened, forming more or less 



