2l6 



PATAGONIAN EXPEDITIONS: ZOOLOGY. 



I append one of a specimen in the third period. None of the specimens 

 are in a very good state of preservation. 



Description of Tadpole. — Length of body about once and a half its 

 width and two-thirds the length of the tail ; nostrils about equidistant 

 from tip of snout and from eye ; distance between eyes more than twice 

 as great as distance between nostrils and much greater than width of 

 mouth ; distance between nostrils shorter than their distance from eye or 

 diameter of the latter ; spiraculum on left side, directed backwards, situated 

 nearer to the eye than to the insertion of the hind leg ; anus median ; tail 

 about four times as long as deep, ending in an obtuse point ; both upper 

 and lower crests confined to the tail and nearly equal in depth ; depth of 

 muscular part of tail at its base a little more than two-thirds of the greatest 

 total depth. 



Beak with black edges, denticulation of cutting edges much finer than 

 of dental rows ; lips papillate, except on the median half of the upper 

 lip ; the series of labial teeth f ; outer series of upper lip long and unin- 

 terrupted, followed by a short series on each side ; the two inner series 

 of lower lip long, occupying the whole width of the lip, the outermost 

 one-third to one-half shorter ; the two outer series uninterrupted, the inner 

 one also continuous or narrowly interrupted in the middle. 



Lines of muciferous ducts cannot be traced on account of the poor 

 preservation of the specimens. 



Color (in alcohol) olive gray, paler underneath, tail indistinctly mottled 

 with dusky. 



The specimen described measures : 



Total length . 



Body . 



Tail 



Width of body 



Depth of tail 



50 mm. 

 20 " 

 30 " 

 14 " 

 8 " 



