worms (SipunculuSj Syllisj Aloiopa) , and tunicates 

 {Doliolum) , 34 



During his travels Krohn entered into friendly relations 

 with many great zoologists of the time, such as Johannes 

 Muller, M. Sars, and Delle-Kyaie, and also the young 

 investigators A. Kolliker, 35 k. Gegenbaur, 36 an( j a. Schneider. 

 Johannes Muller (1801 - 1851) was a great German zoologist, 

 embryologist and physiologist. For a long time he was the 

 editor of the widely distributed journal ARCHIV FUR 

 ANATOMIE, PHYSIOLOGIE UND WISSENSCHAFTLICHE MEDIZIN, 

 in which Krohn published about thirty articles. Part of this 

 information Krohn sent to the editor of the journal in the 

 form of letters, containing information about his last works, 

 and Muller published them in his ARCHIV which he sometimes 

 accompanied by remarks and additions, always with a friendly 

 and positive tone. In those remarks of Mill Her' s, discussions 

 can frequently be found revealing his high regard of Krohn' s 

 scientific activity. 



Krohn willingly related his observations to the zoologists 

 who were working at the same time with him along the sea coast 

 C133) . His objective was to verify his data and to confirm 

 their authenticity, and equally to help also the beginning 

 investigators. His description of the planula hydromedusa 

 Cladonema, Krohn accompanied with the remark that he showed 

 them to Sars and Gegenbaur, thus certifying the accuracy of 

 his observations. 



34. Archives AN SSSR, fund 2, inventory 17, No. 6. The author 

 is deeply grateful to B. E. Raikov. On a commission from 

 him, extracts of reports of conferences of the Academy 



of Science were carried out here and an Archives Certificate 

 received. 



35. "For accurate information about the structure of marginal 

 bodies in medusa," Krohn wrote, "I am grateful to my young 

 friend Kolliker from Zurich" (A. Krohn, "Einige Bemerkungen 

 und Beobachtungen uber die Geschlechtsverhaltnisse bei den 

 Sertularinen," ARCH. ANAT . , PHYSIOL. (1843), pp. 174 - 

 181} . Albert Kolliker was a well-known histologist and 

 embryologist . 



36. Karl Gegenbaur (1826 - 1903) later became a famous 

 comparative anatomist and embryologist. 



563 



