and botany of Lyceum Rishel in Odessa, and in the following 

 year he took the post of director of Odessa Botanic Garden 

 C128) . In 1833 Nordmann together with Rathke, S. S. Kutorgaya 

 and Steven travelled to the Crimea. In the following years 

 he travelled much in the south of Russia; in particular, he 

 led excursions in the Crimea of students of the Odessa 

 Lyceum. When he was sent with a scientific mission to Paris, 

 Nordmann visited with Milne-Edwards the coast of Normandy. In 

 1849 Nordmann came to Helsingfors University, where from 

 1852 to the end of his life he headed the department of 

 zoology. During the period of his scientific activity, 

 Nordmann published fifty-seven works in Russian, Latin, 

 German, French and Swedish on anatomy, embryology, taxonomy 

 and zoography of different groups of vertebrates (mammals, 

 birds, fish) and invertebrates (insects, spiders, crustaceans 

 and worms, mainly the parasitic molluscs, bryozoans and 

 Coelenteratae) ; he also studied botany and paleontology. 



In the previously mentioned MICROGRAPHICAL INFORMA- 

 TION, the results of Nordmann ! s observations on the 

 development of parasitic copepoda Aahtheres peroanon appear, 

 and the larval stages of other related forms (Ergasilus 

 Sieboldi Nordm. , Traoheliastes polycolpus Nordm. and 

 Lernaeoaera cyprinacea) are described. These investigations 

 met the need to explain the systematic situation of parasites, 

 which at that time were related either to molluscs or to 

 the annulated worms, or even to coelenterates. If the relation- 

 ship of some representatives of the mentioned groups Cf° r 

 example, Caligus) to crustaceans was to some extent only 

 probable, then these forms, such as Lemaeocera , which in 

 the adult condition are completely unlike arthropods, 

 remained in their systematic relations mysterious. 



The embryonic development of Aahtheres was described 

 by Nordmann rather incompletely. "On the upper surface of 

 the yolk," he wrote, "is found at first a more transparent 

 region, an4 a granular part of the yolk, having the signifi- 

 cance of a rudiment (KEIM) , turned into round or spherical 

 forms from which the more peripheral give material for the 

 formation of the rudiment membrane (KEIMHAUT) ... The 

 latter completely envelops the yolk and... forms later on 

 the wall of the body of the embryo (p. 78). After referring 

 to the separation of the head and the appearance of the 



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