S. LEPIDOSTERNON. 463 
2. Lepidosternon phocena. 
Lepidosternon phoceena, Gray, Cat. Tort. p. 73, 
and Sh. Rept. ii. p. 40. 
Lepidosternon phocena, Dum. & Bibr. v. p. 507 ; D’Orb. Voy, Amér. 
Meér., Rept. p. 9, pl. vi. figs. 7-11; Strauch, Mél. Biol. Ac. St. 
Petersb. xi. p. 427. 
Differs from ZL. microcephalum chiefly in the following points :— 
Frontal much longer than broad, as long as its distance from the 
end of the snout; supraoculars large, broader than long ; occipitals 
large, nearly as large as the parietals. Sternal platcs all small, 
lozenge-shaped, forming oblique series, without any longitudinally 
dilated ones. 
Argentine Republic. 
a, Ad., stuffed. (Annuli 217+-13.) S. America. Mr. Bridges [C.]. 
3. Lepidosternon strauchii. 
Lepidosternum strauchi, Boettg. Zeitschr. f. Naturw. lviii. 1885, 
p. 221. 
Allied to the preceding. Supraoculars united with the prefron- 
tals. Two hundred and sixty-five annuli on the body and eighteen 
on the tail; an annulus contains twenty-six dorsal and twenty-four 
ventral segments. 
Paraguay. 
4, Lepidosternon infraorbitale. 
Lepidosternon infraorbitale, Berth. Gott. Nachr. 1859, p. 179; 
Strauch, Mél. Biol. Ac. St. Petersb. xi. p. 429. 
Snout very thick, little depressed, not very prominent, with the 
longitudinal grooves feebly marked; rostral rather small, widely 
separated from the ocular; a pair of irregular, suboval preefrontals, 
placed very obliquely and forming together a very short suture; a 
regularly hexagonal frontal, a little longer than broad; a pair of 
very irregular parietals, each about half as large as the frontal ; 
occipitals considerably smaller than the parietals ; eye rather distinct 
through the ocular, which is a little larger than the supraocular, and 
forms a suture with a subocular and a very small portion of the 
second labial; subocular trapezoid, wedged in between the second 
and third labials ; temporal shields very small; three upper labials, 
first and third very small, second very large; mental small, broad, 
quadrangular, followed by a large median chin-shield, on each 
side of which is an elongate, narrow, lateral one; three lower 
labials, first large, second and third very small. Two hundred and 
sixty-four annuli on the body and seventeen on the tail; on the 
body an annulus contains fifty-four segments, twenty-eight dorsal 
and twenty-six ventral. Pectoral shields numerons, small, irregular, 
mostly roundish, forming oblique series. No enlarged anal shields. 
