1887.] ON THE LARYNX OF THE ANUROUS AMPHIBIA. 491 



teeth and the head two frontal tubercles, which, however, are much 

 smaller than in any other species of the group, and followed behind 

 by a broad but shallow frontal cavity. The clypeus is pointed and 

 recurved ; the mandibles without trace of tooth on their outer edge. 

 The thorax is as broad as the elytra, broadly rounded on the sides, 

 slightly narrowed to the base, v\ith acute hind angles ; the surface 

 free from furrows and strongly and sparsely punctured, the punc- 

 tures on the disk larger and transverse-oval or oblong ; on each side 

 of the anterior disk is a small round fovea. The rows of small cir- 

 cular punctures on the elytra are oblitei'ated on the sides posteriorly 

 and on approaching tlie apical callus. The hind tibiae have no trace 

 of spine on their outer edge (only a few short setse), but there is a 

 long spine at their outer apex. The species therefore is intermediate 

 between Burmeister's subgroups a and b. The basal joint of the 

 hind tarsi is not prolonged into a spine. The pygidium is opaque 

 and punctured ; the apical ventral segment very finely punctured, the 

 rest of the abdomen (except the extreme sides) being smootli. 

 The metasternum is punctured on the sides and clothed with reddish 

 hair. 



4. On a hitherto unrecognized Feature in the Larynx of the 

 Anurous Amphibia. By G. J3. Howes, F.Z.S., F.L.S., 

 Assist. Prof, of Zoolog}'^, Normal School of Science 

 and R. School of Mines, S. Kensington. 



[Eeceived June 2, 1887.] 



The general structure of the respiratory organs in the Amphibia 

 was first carefully analyzed by Henle, nearly fifty years ago\ He 

 showed that well-developed laryngeal cartilages are nearly always 

 present, and that the trachea and bronchi, though subject to con- 

 siderable variation, may be supported by cartilaginous elements also. 

 Conspicuous among recent investigators in the same field is Wie- 

 dersheim. He has shown ^ that in the Gymnophiona, as in some 

 Urodeles (e. g. Siren and Amphiuma), trachea and bronchi are well 

 differentiated, and that fully formed cartilaginous rings mav be 

 developed in connection therewith. To him we are also indebted 

 for a description of the larynx of Rana esculenta in all its details \ 

 and for a number of other observations upon the subject generally ; 

 while he has summed up our knowledge of this in his Text-book of 

 Vertebrate Anatomy. Dubois is now engaged upon a searching 

 investigation into the morphology of the larynx. He calls attention 

 in his preliminary notes* to the presence, among other things, of 



^ ' Vergleichende anatomische Beschreibung des Kehlkopfs : ' Leipzig, 1839. 



- ' Die Anatomie der Gymnophionen : ' Jena, 1870. Cf. also his ' Lebrbuch 

 d. Tergleich. Anatomie d. Wirbelthiere.' 



^ Originally in his ' Lehrbuch,' edit. i. vol. ii. 1882, pp. 640-645. 



<* " Ziir Morphologic des Lai-ynx," Anat. Anzeiger, vol. i. 1886. See also Van 

 Beniuieleu, Zoolog. Anzeiger, vol. x. 1887, p. 91. 



