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participation of the stem bud and that they appear later than the 

 corresponding lateral bronchi. Furthermore, the comparative anatomy 

 of the tree suggests to him that the dorsal series are primarily side 

 branches of the lateral bronchi which, in course of ontogeny or phylo- 

 geny are placed back on the stem. In support of this view, he finds, 

 the dorsal buds arising at the same level as the lateral and, appar- 

 ently, in communication with the contour of the latter. Then, he 

 continues, if lateral bronchi are able to give up dorsal branches to 

 the stem, this process repeats itself with the latter series in giving 

 rise to the median bronchi. While he is not absolutely certain that 

 this process takes place in the origin of the dorsal elements, he states 

 that it can be proved with certainty in the formation of the medial 

 series. He shows a schematic series of drawings of the median branches 

 of D. 2, D. 3 and D. 4 in their different stages, giving an apparent 

 transplantation of this median branch upon the stem bronchus. Like 

 the median series Narath also believes that the ventral bronchi (the 

 Ventro-accessory of Aeby) are branches which are given up from the 

 lateral branches to the stem. In one rabbit embryo Narath was able 

 to show a relationship between Ventral 1, the infracardiac bronchus, 

 and Lateral 1. He says further: „Der Zusammenhang der Knospen ist 

 ein primäres Verhältnis und kein sekundäres. Und wenn weiter ein- 

 gewendet werden sollte, die Knospen hängen deswegen so innig zu- 

 sammen, weil bei der erwachsenen Lunge die Bronchien so enge bei- 

 sammenstehen, so würde ich auch wiederum gerade diesen Befund bei 

 der erwachsenen Lunge als für die AEBY'sche Ansicht sprechend ver- 

 werthen." In a word, while not absolutely pledging himself to this 

 view, Narath believes that there are but one primary set of bronchi, 

 namely the lateral, and that the other three series, the dorsal, ventral 

 and medial, originate either directly from these branches as in the 

 case of the dorsal and ventral groups, or indirectly as in the case of 

 the median bronchi which arise from the dorsal series. They are then 

 given up on to the stem bronchus. 



Moser 1902 says for the vertebrate lung in general that "das 

 Verzweigungssystem der Kanäle innerhalb der Lunge ist stets und aus- 

 schließlich ein mouopodiales". It must be remembered, however, that 

 Moser's material on the mammalian lung was very limited and con- 

 fined to older embryos which were studied by means of sections in- 

 stead of corrosions and reconstructions. Some criticism might be made 

 of her comparative material especially in view of the more exact 

 methods used by Hesser in the same field. 



Blisnianskaja 1905 in the human lung states that "die Bronchial- 



