August 18, 1911] 



SCIENCE 



213 



The Vienna correspondent of the Journal 

 of the American Medical Association writes 

 that at present there are two medical posts 

 vacant in Austria : one at the clinic for in- 

 ternal medicine in Innsbruck, from which 

 Ortner was called to Vienna to succeed von 

 Striimpell, and the other at the pharmacologic 

 institute of the German university in Prague. 

 The latter has become vacant through Pro- 

 fessor Pohl's acceptance of an appointment at 

 Breslau. The following scientists have been 

 recommended in the order named for the va- 

 cant post : for Innsbruck, Professor Pf eift'er 

 from Graz, well known for his researches on 

 serology, hematology and diseases of the 

 lungs; Docent Dr. Schmidt (Vienna) and 

 Professor von Tabora from Strasburg and 

 also Professor "Walks from Prague; for the 

 pharmacologic institute. Professor Cloetta 

 from Zurich, Professor Wiechowski, who is 

 at present an assistant of Horst-Meyer in 

 Vienna, and Professor Jodlbauer in Munich. 



Mr. Herbert Bolton, P.G.S., curator of 

 the Bristol Museum of Natural History, has 

 been appointed reader in paleontology in the 

 University of Bristol. 



Dr. Samuel Oppenheim, of Prague, has 

 been elected professor of astronomy in the 

 University of Berlin. 



DISCUSSION AND COBBESFONDENCE 



concerning the " NEMATOCYSTS OF MICRO- 

 STOMA " 



Professor Glaser in Science of July 14, 

 1911, has criticized my recent paper on 

 " Nematocysts of Microstoma." ' In the first 

 place he indicates that I have made a quota- 

 tion from his paper and given credit for it to 

 Boulenger. This was a piece of carelessness 

 on my part. That it was an inadvertence is 

 shown in that the page numbers given refer 

 to Glaser's article, to which I meant to give 

 credit. I greatly regret that this blunder has 

 been made and I am grateful to Professor 

 Glaser for calling my attention to it. 



^Biological Bulletin, Vol. XX., No. 5. 



My critic continues by saying, " Professor 

 Kepner states that the cnidophages of aeolids 

 deliver their nematoeysts to the cnidocyst, 

 whereas the endodermal cells of Microstoma 

 deliver their nematoeysts to the mesoderm. 

 Unfortunately for the analogy, both Grosvenor 

 and I have shown that the cnidophages after 

 engulfing a certain number of nettles, meta- 

 morphose directly into cnidocysts." ' I had 

 attempted to make no analogy in this case nor 

 was I concerned with the manner in which the 

 cnidocyst was formed. I had attempted to 

 make a comparison. The cnidophages of 

 SBolids by metamorphosing to form the 

 cnidocysts do not involve the mesodermal cells 

 and thus may be compared with the endo- 

 dermal cells of Microstoma which deliver the 

 nematoeysts to the mesoderm. 



Professor Glaser in the third place criti- 

 cizes me for quoting Grosvenor in support 

 of the idea that the nematoeysts of seolids are 

 of defensive value, and at the same time over- 

 looking the work of Cuenot and Glaser which 

 showed that the " defensive value of the 

 nettles is slight if not negligible." I had not 

 overlooked this work of Cuenot and Glaser on 

 the nematoeysts of seolids. Despite this nega- 

 tive evidence I am constrained to believe that 

 the nematoeysts of Microstoma are of defen- 

 sive value. 



Finally my critic states that I have raised 

 the question whether seolids have acquired 

 their method of dealing with nematoeysts of 

 ccelenterates through flatworm ancestry. This 

 question was suggested. Professor Glaser, 

 however, is unfair to me in not stating that I 

 had placed by the side of this the alternative 

 question whether we had here cases of parallel 

 development. Two questions, not one, were 

 thus raised by me, and I feel quite unready 

 to defend either hypothesis. 



Giving credit to whom credit is due, the 

 fact remains that the endodermal cells of 

 Microstoma collect the nematoeysts of Hydra 

 to deliver them to mesodermal cells. Certain 

 mesodermal cells transport these nematoeysts 

 to and orient them at the ectoderm. 



This intricate process has no meaning un- 



^ Science, Vol. XXXIV., July 14, 1911, pp. 51-2. 



