160 



BULLETIN 58;, UNITED STATES NATIONAL MUSEUM. 



sp- 



an: 



being lower labial. These are described as first, second, third, etc., 

 proceeding from the outer border toward the beak in both the upper 

 and lower sections of the Hp. The first series, either in the upper or 

 155 loG lower section, may be mar- 



ginal or may be within the 

 border, which is then occu- 

 pied b}^ fleshy papillae. The 

 arrangement of the series is 

 expressed by a formula: §, 

 for instance, mdicating the 

 number in the upper and 

 lower sections, the line cor- 

 respondmg to the beak. 



By spiraculum (figs. 155- 

 156) is understood the open- 

 ing or tube by which the 

 water is expelled from the 

 bronchial chambers. In our 

 species it is located either on 

 the left side or in the me- 

 dian line on the breast. 



The anal opening (figs. 

 155-156) is also a tube situ- 

 ated at the beginning of 

 the tail either in the middle 

 line or laterally beside the 

 origin of the lower caudal 

 crest. 



The openings of numerous 

 sensory ducts form more or less complicated systems of lines on head 

 and body, and are of some systematic value. A glandular streak 

 extending from the nostril toward the eye is the lachrymal canal. 



Figs. 155-156.— Lower view of tadpoles, showing lo- 

 cation OF SPIEACULUM AND ANAL OPENING. 155, DiS- 

 COGLOSSOID (COSTATE) TOAD; 156, HyLA. Sp, SPIRACU- 

 LUM; an, ANxrs. (From Boulenger, Proc. Zool. Soc 

 London, 1891, p. 596.) 



Figs. 157-159.— Mouth of tadpoles. 10 X nat. size. 157, Bombina salsa; 15S, Hyla arborea. 



15 X NAT. SIZE. 1.59. BUFO BUFO. (FrOM BoULENGER, PROC. ZOOL. SOC. LONDON, 1891, PL. XLVII, 

 FIG. 5a; PL. XLVI, FIGS. lA AND 4A.) 



