76 Contribution towards the knowledge of snakes in Brazil 
Yellowish brown above, there being generally on either side 
a series of complete or divided blotches which are spaced from 
each other and may be narrow, triangular, quadrangular or li- 
neal, placed in opposition to or alternating with those of the 
other side. Sometimes these blotches are not found or they may 
be nearly imperceptible. Head also yellowish brown without 
blotches and having no streak behind the eye. Belly light yellow 
or whitish, entirely uniform or, in some specimens, slightly dotted 
with light brown on the side of the ventrals. Young vellowish 
pink to brownish pink above, with very imperceptible blotches, 
belly uniform yellowish white. 
Dimensions — The type (specimen 92 n.º 1.996) measures 
135 mm. total length, the tail measuring 98 mm. Among all the 
specimens the largest is an S£ which' has a total length of 1 
meter, the tail measuring 118 mm. Of the 203 specimens examined 
the 10 largest are 2 9. 
Habitat — All specimens are from the «Queimada Grande » 
Island on the coast of the State of São Paulo, about 40 miles 
S. W. of bay of Santos. In accordance with observations which 
I have made concerning the species of snakes found on the 
several islands and points on our coast, I am convinced that 
Lachesis ainsularis is found only. on «Queimada Grande » Island. In 
relation to its small surface this island is assuredly the point 
of the globe most thickly populated with snakes. 
Type — Specimen Z in the Butantan Institute snake collection 
under n.º 1.996. Plate IV, in three colors, faithfully reproduces 
the colouring of that specimen which is one of the darkest of 
the collection. This snake was killed shortly before changing its 
skin. 
Notes — This species, considered from a purely systematic 
point of view appears to be closely related to other Crotaline 
which frequently occur in Brazil where they are generally known 
respectively: by the common names of « Jararaca» and « Caiçaca ». 
However, before establishing the differences existing between 
them, I shall hurriedly make some comments on the «Jararaca » 
and the «Caiçaca» using some summarized data from a study 
which I intend to publish shortly on the points of distinction' 
between our several Lachesis, in addition to the excellent mo- 
nograph of Miss J. B. PROCTER (1º) concerning variations of Lachesis 
atror (L.). à a 
The identification of our «Jararaca» with the Lachesis lan- 
ceolata described by De LacEPEDE (19) for Martinica and perhaps 
for Dominica and French Guiana, and our «Caiçaca» with the 
Lachesis 'atrox (L.), seems to me to be a question still open 
(1) Miss J. B. Procrer — “On the variation of the Pit-viper, Lachesis atrox” — in Proc, of 
Zool. Soc. of London, 1918; vol. I and Il; pp. 1638-182. 
(18) De LaokrkDE — Histoire Naturelle des Serpentes”, 1879; p. 121; and in A, G. Desmarest — 
“Oeuvres du Conte Lacépêde”, 1828; pp. 223-252; pl. 29, fig. 1. 
