GEORGE B. CHAPMAN 151 



CROWELL: I have thought for many years, hke Chapman, that 

 this turning inside out of so fine a tubule probably violated the rules 

 of hydraulics. It would be very nice to see a diagram of his inter- 

 pretation, perhaps compared with the conventional interpretation. 



CHAPMAN: I may have to get a flyrod out of my car. 



SLAUTTERBACK: We have often seen these stenoteles when 

 they have been interrupted by the fixative at various times during 

 the firing process. It can be seen clearly that the narrow part of 

 the tubule evaginates through the broad base, or butt, and expands 

 in diameter as it does so. Our observations would support the ele- 

 gant polarized light studies of Picken and Robson, whose interpre- 

 tations ought not to be neglected in this discussion. Furthermore, 

 since the base of the tubule is attached all the way around the 

 orifice of the capsule I cannot imagine a route of exit if you pro- 

 pose to get it out sideways. 



WOOD: Nematocyst discharge is probably pretty much the same 

 for all nematocyst types. Using light microscopy, many people have 

 observed the tubes coming out from the inside of the discharging 

 holotrichs. To me, this is pretty strong evidence that the same 

 sequence occurs in the other nematocyst types. I would agree with 

 Dr. Slautterback. 



CHAPMAN: My statements were made to explain how the tu- 

 bule might be discharged // the hook and swelling did in fact serve 

 the speculated functions. Most of the evidence supports the tubule 

 eversion hypothesis even though this eversion would involve a 

 nearly impossible physical feat. 



