442 W. DE MORGAN AND THE LATE G. HAROLD DREW. 



Experiment, July 18. Tissue died. 



Experiment, July 19. Tissue formed, but died next day. 



Experiment, July 22. Tissue died next day. 



Experiment, July 23. Tissue died next day. 



Experiment, July 25. Small masses of tissues were formed, and secreted 



perisarc. They were alive 4 days after formation. 

 Experiment, July 27. Most of the large pieces of tissue died, but small 



lumps were alive 4 days later, and coenosarcal outgrowths had 



sprouted. 

 Experiment, August 1. Small masses a fraction of a millimetre lived, 



showed perisarc and were alive 2 days later. 

 Experiment, August 2. (a) Most of the tissue formed was alive on 



August 3rd ; much died by 7th. Outgrowths were formed, with 



vertical branches by 11th, but were sickly. 

 Experiment, August 2. (6) Many small spheroidal masses formed, and 



developed perisarc, but not coenosarcal outgrowths. They were 



alive 5 days later. 



Pennaria tiarella. 



Experiment, July 26. Cell fusion and aggregation commenced at once. 

 Small masses formed in an hour, and fused into tissue. In about 

 4 hours masses 1 mm. in diameter have formed. Next day perisarc 

 formed, and in 3 days outgrowths were developed, but at the same 

 time many of the larger masses died. In 5 days hydranths appeared 

 on the outgrowths with characteristic tentacles. 



Experiment, August 3. In this experiment only stem material was used. 

 Fusion was rapid, and in about an hour a cake was formed. Next 

 day perisarc appeared, and outgrowths commenced. Another mass 

 from this culture in two days developed a hydranth. In 5 days 

 all masses of this experiment except 4 were dead ; the survivors 

 developed outgrowths and were then preserved. 



Many other valuable observations are included in Wilson's paper, 

 but these experiments are the only ones with which we are immediately 

 concerned. The paper also contains a full account of the literature 

 on the subject of the behaviour and the regenerative properties of dis- 

 sociated somatic cells of various species of animals, and accordingly a 

 review of this literature will not be repeated here. 



