34 



Dr. Wilder observed that : »ein vollständiger Mangel von Lungen 

 und Luftwegen vorkommt« in 



y>Desmognathus fuscus, 



Desmognathus ochrophaeus, 



PletJiodon erythronotus, 



Gyrinophilus porphyriticusa. ' 

 Professor Camer ano has found that: 



1. »le Spelerpesfuscus manque totalement de poumons, de trachée, 

 de larynx et d'aditus ad laryngem« 



2. »la Salamandrina perspicillata a l'appareil pulmonaire et 

 trachéo-laryngien tout à fait rudimentaires et ne fonctionnant pas«. 



The author of these lines has had the opportunity to investigate 

 these matters in the following species 



Desmognathus auriculatus Cope from Savannah, Ga. and Florida. 



Plethodon glutinosus (Green) from Savannah, Ga. 



Manculus quadridigitatus (Holbrook) from Florida and 



Amblystoma opacum (Gravenh.) from Savannah, Ga. (coll. Capt. 

 C. Eckman). 



The first two of these species belong to genera in which Wilder 

 has already stated the absence of the lungs and there is no trace to be 

 seen in these species either of lungs or of larynx. A median longi- 

 tudinal groove is the only remaining rudiment of the aditus ad 

 laryngem. In preparing transverse sections, for instance, oi Plethodon 

 glutinosus this groove can be most easily seen and followed from sec- 

 tion to section, but does not extend so far back as to the anterior part 

 of the laryngeal muscles. In some specimens it is however difficult 

 to observe this groove, at least without preparing sections. The trans- 

 verse laryngeal muscles (»eigentliche Kehlkopfmuskeln«, Wilder) are 

 well developed in Plethodon glutinosus and are in the middle, where 

 they meet, separated by a narrow, bvit tight and plainly visible strip 

 of connective tissue at which the muscles insert themselves. This 

 connective tissue which, as Wilder says, may represent the »Rest 

 des verloren gegangenen Kehlkopfes« is not so broad and large as in 

 Desmognathus fusca according to Wilder' s figure (fig. 3 1. c.) ; it is 

 however well developed and strong enough to be the point of insertion 

 for the muscles, which is quite contrary to the case in Plethodon ery- 

 thronotus where Wilder did not find any »mit I>indegewebe gefüllten 

 Zwischenraum« between the »beiden lateralen Hälften, welch letztere 

 direct auf einander stoßen« (1. c.) In dissecting Manculus quadridigi- 

 tatus no trace of lungs etc. can be seen. Neither in dissecting nor in 

 preparing microscopical sections with the microtome have I been able 



