80 PROCEEDINGS OF THE NATIONAL MUSEUM. 



their general appearance in the water suggesting a small catfish. 

 Larva? of Dlemyctylus are maculate at an earh^ age, have a dark line 

 through the eye, and when of fair size show the red lateral spots, all 

 of whicli characters the larva' of the cave salamander lack. In one 

 larva of the newt examined, the upper series of larval areas is 6 in 

 num))er, the middle, 12, and the lower series obsolete. Desmognathus 

 larva^ arc characterized by an upper series of 10 to 11 large clear 

 areas whicli are distinctly dorsal in position and run together on the 

 taih (The number given includes onh' those anterior to the point of 

 union.) As this series of areas is distinctly lateral in ni<iculieau<his^ 

 the separation of the larvaj of these two species will not be difficult. 



In the genus SiJeJerpex itself, the differentiation is as easy in the case 

 of the species we have studied. Not a sutficient number of lovgu-audus 

 larvii? have been seen to warrant a definition. This is particularly 

 unfortunate, as there is no doubt that it is most close!}" related to the 

 present species. In one large larva of longieaudns the upper series of 

 clear areas had disappeared, the middle one had about 16 to 18 spots, 

 and the lowest series 12. If these numbers are constant they furnish 

 a means of distinguishing these nearly related larva'. In larva^ of 

 lovgicaudus that have attained fair size the vertical bars on the tail are 

 apparent, thus making this character available for identifying larva? 

 as well as adults. 



Only large larvae of guttoUnedtHi^ \va\q been seen. These are con- 

 spicuously marked. In the upper series of clear areas there are four, 

 and the middle and lower series form continuous light bands on the 

 sides of the animal. The Ixdly is longitudinally striped, this character 

 serving to separate these larvic from any others of the genus here 

 considered. 



The young iarv;e of hilineatxix. have the upper series of larval areas 

 very conspicuous and the lower two series not evident. The upper 

 of these is developed to some extent later. Also hUhieatus larva? 

 have the dorsal area light in very early as Avell as later stages, and 

 there are never as many nor as prominent blotches on it as in litacull- 

 caudns. Spelerjyes ruher is easily distinguished in all stages. The 

 older larva? are, up to the time of transformation, almost uniform!}^ 

 vermiculated with pigment, while the young larvte, in addition to 

 practical luiiformity of color, have a decided character in the great 

 number of areas in the middle series, namelv, 28. These resemble 

 the stitching of a sewing machine, so close together are the}', and 

 appear as a finely dotted line on the side of the larva?. In this series 

 it wall be remembered macuUcaudas has oxAj 13 to 15. These 

 series of inunaculatc areas on the side of the larval salamanders seem 

 to form a good character for the detei-mination of species. Therefore 

 we offer tentativel}" a table embodying the results of the study of a 

 few species as a further aid in distinguishing the larva' of the cave 

 salamander. 



