228 



HYDROZOA. 



skeleton is calcareous, and its general substance is composed of a 

 characteristic, cancellated or tubulated ccenosarcal tissue, closely 



resembling the ccenosarcal 

 tissue of Parkeria. The tu- 

 buli of the general ccenosteal 

 tissue have a radial direction 

 from the centre to the cir- 

 cumference, as in Parkeria, 

 but there is no marked ar- 

 rangement into concentric 

 layers. As seen in cross-sec- 

 tions (fig. 113, a) this tubu- 

 lated tissue exhibits a char- 

 acteristic netted appearance. 

 The general cancellated tissue 

 of the skeleton is traversed by 

 numerous comparatively large 

 radiating tubes (fig. 113, /), which open on the surface by the 

 rounded apertures above spoken of, and which may be regarded as 

 zooidal tubes. These tubes, in some cases at any rate, are of differ- 



Fig. 112. — A specimen of Stoliczkaria granulata, 

 of the natural size, from the Triassic rocks of Kash- 

 mir. The surface of the specimen is much worn, 

 but shows the apertures of the zooidal tubes. 

 (Original.) 



co A c co B c 



Fig. 113. — Minute structure of Stoliczkaria. A, Section of the skeleton taken tangentially to 

 the surface, enlarged twenty-five times, showing the general cancellated ccenosarcal tissue (c) and 

 the transversely-divided zooidal tubes (t) with their reticulate columellas (co); b, Vertical section, 

 similarly enlarged, the letters as before. (Original.) 



ent sizes, and correspond with the " gastropores " and "dactylo- 

 pores " of the Stylasterids, and each is provided with a reticulate 

 central style or "columella" (fig. 113, co). In cross-sections the 



