3l6 RESEARCH IN CHINA. 



single rows between the apertures. On the average about 8 surround each cell, 

 but as they vary greatly in distribution sometimes more (as many as 12 or 13) 

 and sometimes less can be counted. They are also very irregular in point of size, 

 some having a diameter twice or even three or four times as great as others. Often 

 they appear to be in two well-marked grades of size, but sometimes another inter- 

 mediate grade can be recognized, and it seems likely that there is no absolute 

 classification to which they can be reduced in this respect. While in a general way 

 the large and small granules appear to be regularly distributed, no definite system 

 or arrangement can be made out. In sections longitudinal to the tubes the thickened 

 or mature region is quite shallow, about twice the width of the apertures. The 

 latter, however, here appear of much smaller diameter than in the transverse section, 

 being only about half as wide as the intercellular granuliferous spaces, which there- 

 fore present nearly square areas in thin sections cut longitudinally. 



This form is structurally very closely related to Rhombopora lepidodendroides, 

 but is clearly distinct from that widely distributed American species. Kayser iden- 

 tified Rhombopora lepidodendroides in the Lo-ping fauna. From this Batostomella 

 meekana seems to be distinct, as it without much question is if the Lo-ping form 

 is correctly identified. Of the two species of Rhonibupora described by Waagen 

 from India, it may be distinguished from R. polyporata by the much smaller number 

 of granules. Though more similar to R. obliqua it also differs in several particulars. 

 It is a more robust form. The cells are more nearly circular and apparently of 

 larger size, since, according to Waagen's figure, only about three occur longitudi- 

 nally in 2 mm. Furthermore, Waagen states that the granules are all of a size in 

 his species, which is conspicuously not the case in the one under consideration. 



Locality and Horizon. Pennsylvanian (Wu-shan limestone) ; near Ta-ning- 

 hien, East Ssi-ch'uan (station 4). 



Fistulipora waageniana Girty. 



Plate 28, Figures 3-5. 

 Fistulipora waageniana GIRTV, 1907, Proc. U. S. Nat. Mus., vol. xxxm, p. 44. 



Of this species our collection contains but one specimen, which displays the 

 following characters : The form is that of a hollow cylinder, the diameter of which 

 is 25 mm., the length of the fragment being 45 mm. The thickness of the zoarium 

 varies somewhat, but has an average of about 5 mm. It can not be determined 

 whether the original shape was incrusting, hollow cylindrical, or solid cylindrical. 

 So far as can be observed, there is no epitheca upon the inner surface, nor is there 

 any flexing of the cells toward a point of origin. From this circumstance it can 

 perhaps be inferred that the original form was a solid cylinder, of which the axial 

 portion, including the immature region of the cells,has bysomemeans been destroyed. 



In thin sections the zooecial tubes are seen to occur about four in the space of 

 2 mm. Their distribution, however, is quite irregular. They have very thick walls, 

 which in some cases are almost in contact and in others are separated by distances 

 equal to about the inner diameter of the tubes. In the region of maculae their 

 distance is sometimes two or three times the diameter. The cells are of course 

 nearly circular, and as a rule separated by rather large mesopores in single rows. 

 Near the surface the spongy tissue of the mesopores gives place to solid investment, 

 in which, though the inner portion of the tubes has still a circular section, the outer 

 boundary, more or less clearly shown, is sharply polygonal. A lunarium is as a 

 rule entirely absent, though in rare cases indistinct but certain traces of the struc- 

 ture can be observed. It is also more or less regularly developed in young stages. 



