rudiments of the extremities, Nordmann turned to the 

 characteristics of the nauplius larva, whose structure 

 becomes complicated after moulting. 



Its central point was the description of the larval 

 stage of Lemaeooera oyprinaoea . The adult animals of 

 this genus were already known to Linnaeus; they are 

 characterized by a sacculated unopened body, deprived of 

 extremities and organs of sensations (Figure 37, A). "If 

 naturalists," Nordmann wrote, "are astonished at the 

 structure of the body of the mature animal of this kind, 

 their astonishment will be more natural when an opportunity 

 arises for them to observe the young animals. It can hardly 

 be imagined that there is anything more striking than an 

 offspring having absolutely nothing in common with its 

 parent. Before my eyes the egg receptacle in the mature 

 animal was ruptured, and the embryos set free. I saw young 

 animals exactly the same as I represent them in the drawing 

 (Figure 37, B) ; they have extremities, antennae, and even 

 bright red eyes" (128). 



Nordmann 1 s observations met, according to him, decided 

 distrust from Berlin zoologists to whom he demonstrated 

 the nauplius larvae of Lemaeooera oyprinaoea. Later the 

 significance of this discovery was universally recognized 

 (129) . 



After some years Nordmann published a small embryological 

 work concerning the Black Sea bryozoan Tenchca zosterioola A 7 

 In one zooid Nordmann found from four to seven eggs and 

 saw the penetration of the spermatozoids in the female cells 

 through an opening in their base. Later he saw the embryos 

 hatched from the eggs swimming by means of cilia and finally 

 settling in the seaweed Zostera. "As far as it is possible," 

 Nordmann wrote, "I observed the transformation of the young 

 animals and the development of polyps from them." Greater 

 significance was possessed, however, by other embryological 

 work of Nordmann' s on the development of molluscs. 



17. A. v. Nordmann, "Recherches microscopiques sur l'anatomie 

 et le developpement du Tendra zosterioola, espece de 

 polype de la section des Bryozoaires , " ANN. SC . NAT. 

 ZOOL., 11 (1838), pp. 185 - 191. 



530 



