229, CHELYDID&. 
Mental barbels shorter than the diameter 
of the eye; intergular shield longer than 
its distance from the abdominals ...... 5. radiolata, p. 225. 
II. Skin of median upper surface of head undivided. 
Suture between the pectoral shields longer 
than that between the abdominals...... 6. rufipes, p. 225. 
Suture between the pectoral shields shorter 
than that between the abdominals .... 7. wagleri, p. 225. 
1. Hydraspis hilarii. 
Phrynops geoffroyana (non Schweiyg.), Wagl. Syst. Amph. p. 135, 
pl. v. figs. xlviii.—li. (1880), and Icones, pl. xxvi. (1833), 
Platemys geoffreana, juv., Dum. § Bibr. i. p. 421 (1835). 
hilarii, Dum. § Bibr. p. 428; Guichen. in Casteln. Voy. Amér. 
Sud, Rept. p. 7, pl. i. (1855) ; Burmester, Reise La Plata, ii. 
p. 521 (1861). 
Hydraspis hilarii, Gray, Cat. Tort. p. 40 (1844), and Sh. Rept. i. 
p- 57 (1855). 
Platemys geoffreyana, part., Hensel, Arch. f. Nat. 1868, p. 350. 
Spatulemys lasale, Gray, Ann. § Mag. N. #. (4) x. p. 463 (1872), 
and xi. p. 73, pl. il. (1873). 
Carapace with a very feeble vertebral keel, which may disappear 
in the adult; dorsal shields of young not gibbose, but with con- 
centric and radiating strie. Front lobe of plastron broader than 
hind lobe; intergular shield as long as its distance from the 
abdominals in the young, shorter in the adult; suture between the 
pectorals much shorter than that between the abdominals. Median 
region of upper surface of head divided into irregular shields, 
among which a small azygos frontal is constantly distinct: parietal 
bones above as wide as the diameter of the orbit; mental barbels 
at least as long as the diameter of the eye, club-shaped, narrowest 
at the base. Olive above, edge of carapave yellow; some of the 
marginals usually with one or two small black spots; plastron and 
lower surface of marginals yellow, with black spots disposed more 
or less symmetrically ; a black line on each side of the head and 
neck, passing through the eye ; lower surface of head and neck, and 
tympanum, yellow ; each barbel with a black ring; a black line on 
each side of the throat, behind the barbels, sometimes connected 
with the lateral line on the neck; lower surface of neck with a few 
black spots ; inner surface of limbs yellow, with one or more black 
spots or streaks ; hinder side of thighs with a black band, 
Length of shell 34 centim. 
South America between the Amazons and the Parana. 
a,b-f. 3%, her. Rio Grande do Sul. Dr. H. v. Ihering [C.1]. 
& yg., spr. 
g. 3, skel. Rio Grande do Sul. Dr. H. v. Thering [C.]. 
h. 3, stiid. R. Parana, Prov. Col. Perez de Lasala [ P.]. 
Corrientes. (‘Type of S. lasale.) 
a. Q, spir. Buenos Ayres, W. White, Esq. [C. ]. 
k, 3, stfid. 5 
