INVESTIGATIONS ON PARAGUAYAN BATRACHIANS. 
band extends from the tip of the snout through the eye to the arm, en¬ 
closing the nostril and surrounding the upper part of the tympanum ; 
upper lip broadly edged with a dark brown band, which is punctulated 
with dirty-white ; between this marginal and the canthal band runs a 
greyish-white stripe to the arm. Tympanum chestnut-brown, bordered in 
front with a short crescent-shaped white line and with a longer one 
behind; the former isolate, the latter connected with the white stripe of 
the jaw,* — quite as on Leptodactylus mystacinus Burm. Limbs with 
narrow, not sharply pronounced cross-bars. Immediately above the anal- 
cleft stands a white linear spot in the centre of a more or less distinct 
rhomboidal white marking, from the outer corner of which a longitudi¬ 
nal white stripe or a punctulated white row, bordered above and below 
wdth black, extends along the hinder side of the thighs.** Lower surface 
light brownish-white, immaculate ; lower lip and sides of the throat to 
the arm marbled with brown. 
The male has the same colour and markings as the female, with 
that difference that the upper surface of the head and the back between 
the inner lateral folds are uniform rose-coloured, through which 
colour the dark marking between the eyes is shining. The lateral lines 
and spots are rather indistinct. Limbs narrowly cross bared, its browm 
ground-colour covered with a faint rosatre breath. Beneath uniform yel¬ 
lowish-white ; lower lip greyish margined. 
This species is very closely allied to Leptodactylus mystacinus 
Burm., from which it differs by the slender form, longer and narrower 
head, more acuminate snout, broader interobital space, longer hind limbs, 
more pronounced tubercles of the sole, the elevated middle line and more 
distinct tarsal fold, the two black, above white-edged glandular folds on 
each side of the body and the white longitudinal stripe of the thighs. 
It could be assumed that the above described two specimens of 
Leptodactylus mystaceus Spix represents only the young state of Lepto¬ 
dactylus mystacinus Burm. and that the formerly described male of the 
latter species differs only for that reason, because it stands on the top of 
its breeding season, to which time the lymphducts are quite filled out, so 
that the glandular folds of the flanks, the fine tarsal fold, the elevated 
middle line of the back and more or less also the plantar tubercles have 
disappeared. But the mentioned differences are much to great as that 
they could be regarded as characters of the young age and seems to be 
quite sufficient to determine a distinct species. 
* All this markings are sharply pronounced on Spix’s type. 
** Already Spix remarks: «striæ supra et ad latera ani albicantes.» 
