e a ch side b ia ish gray, passing b en e a th in to yeilowish v b ite . A series o f very irre g u la r transverse
spots cross th e yellow median p o rtio n o f th e back, a n d th e re are others o n th e sides ; an d these
two series becoming confluent on th e tail, form, with th e yellow g ro u n d , a ltern ate h a lf rin g s o f
th e two colours. T h e u p p e r p a r t o f th e legs has similar bands. T h e whole o f th e th ro a t, belly,
a n d inferior surface o f th e limbs an d ta il are yeUowish white. T h e re are numerous small
b lackish spots over these p a rts which are more d is tin c t an d lin e a r on th e th ro a t, an d becoming
pale r, smaller an d ro u n d on th e belly.
DIMENSIONS.
Inches. Lines.
Length of the head ................. ........... 1 0
of the b o d y .............................. 2 2
of the ta il................................... 3 8
Total length 7 0
Length of anterior extremity ............ 1 1
of posterior extremity............ 1 6
Taken a t P o rt Desire, on the coast of Patagonia.
D i p l o l iE m u s B i b r o n i i . 3 I i h i .
P late X I.
Squamis capitis planis; caudd corpore cum capite hreviore.
Habitat, P o rt Desire.
D e s cm p tio n .— H e a d th ick a n d clumsy, lo n g er th a n it is broad, muzzle obtuse, supra -orbital arches
slig h tly elevated. N o strils as in th e forme r species, in size, form, a n d s itua tion. E a rs sub-
trian g n la r, th e m arg in simple. N e c k considerably co n tra c ted , w ith a lo n g itu d in a l fold on
ea ch side, a n d a d is tin c t transve rse fold on th e th ro a t. Body ra th e r broad, slightly depressed,
p erfec tly even, w ith o u t a n y ce n tra l cre s t or elevation. T h e tail is sh o rte r th a n th e h e a d a n d
body, slightly tria n g u la r a t its base, ta p e rin g ic g u la rly to its ex trem ity . L im b s o f mo d era te
l e n g th ; th e toes o f ea ch foot lo n g er th a n in D . Bibronii, a n d th o se o f th e fore-feet more
u n eq u a l, th e th ird bein g th e longest, th e n th e fo u rth , th e second, th e fifth, an d th e first. T h e
foro-logs p lac ed ag a in st th e side reaches to ab o u t tw o -th ird s o f th e distance b e tw e en th e
sh o n ld er a n d th ig h ; th e h in d e r fo o t p la c ed in th e same m an n e r re ach e s to th e axilla.
T h e scales o f th e h e a d are q u ite flat, a ch a rac ter in which th is species differs rema rkably
from th e former, a lth o u g h in th e ir n um b e r an d a rran g em en t th e y are v e ry similar. T h e occip
ita l scale is flat an d hexagonal. B etween th e labial scales a n d th e snborhital, th e re are, in
ad d itio n to th e re g u la r series o f larg e r supra labial scales, a t lea st th re e d is tin c t series o f smaller
o n e s ; whereas in D . D a rw in ii th e re is b u t one.
T h e scales o f th e temples, th e neck, th e body, th e limbs a n d th e tail, arc similar to those
i :