GENERA OF FAVOSITIDyE. iii 



Gemis Vermipora, Hall, 1874. 



(Twenty-sixth Annual Report on the State Cabinet of New York, p. 109.) 



Professor Hall defines this genus as follows : " Bryozoum 

 growing in ramose branches, which are composed of small cell- 

 tubes growing upon one another side by side, without inter- 

 tubular or cellular substance, and destitute of rays or trans- 

 verse partitions within the tubes. Tubes diverging from the 

 centre of the branch, gradually diverging, and opening upwards 

 on the exterior surface ; each tube forming the apex of the 

 branch at the time of its origin, and giving place to succeeding 

 cells in its diverging outwards." 



More recently, Dr Rominger has published the following 

 definition of Vermipora, Hall, (Rep. Foss. Cor. of Michigan, p. 

 68, 1876):— 



" Ramified twigs, composed of contiguous, sub - parallel, 

 cylindrical tubules, multiplying by lateral gemmation, slowly 

 diverging in their parallel ascending course from a central 

 imaginary axis, and becoming disjunct near their peripheral 

 ends, which project on the surface as single proboscidal 

 siphuncules. Tubes intersected by remote transverse dia- 

 phragms, and connected by lateral pores. Vertical radiating 

 crests not observed." 



To the above generic diagnosis Dr Rominger adds the fol- 

 lowing remarks : "Mr Hall places these forms with the Bryozoa, 

 and gives of their structure a description different from mine. 

 He has overlooked the principal Favositoid characters of the 

 tubes, diaphragms and lateral pores ; but I think these organs 

 can be found in his specimens as well as in those I have under 

 consideration." 



Ois. — Not having had the opportunity of personally examin- 

 ing any unquestionable examples of this genus, and having no 

 knowledge of its microscopic structure, it is impossible for me 

 to supply any data which might serve to clear up the discrep- 

 ancies between the generic diagnoses given by Hall and 



