370 BULLETIN 17 7, UNITED STATES NATIONAL MUSEUM 



lightening on chin, this color darkening on belly where it becomes 

 heavily suffused with indigo; a remnant of a pale lateral stripe from 

 the labials along the sides of the neck on the second and third scale 

 rows, and another on the lower half of the first scale row, both these 

 fading out on the first third of the body; a large black spot at the 

 outer border of each ventral plate, also continued on the tail nearly 

 to its end; a median series of indistinct black spots on the third to 

 the seventeenth ventrals, thereafter appearing as a pair of black 

 spots gradually diverging from the center posteriorly and becoming 

 quite small and indistinct just anterior to the vent; tail black above, 

 with a faint continuation of the light dorsolateral stripe; lower part 

 of tail pearl-gray with a mottling of small indigo spots. 



"Dimensions. — Head and body, 406 mm., tail, 301 mm. 



"Paratypes. — There are five additional specimens, M.C.Z. 37669-72, 

 and U.S.N. M. 95116, taken at the same time and place as the type. 

 In addition, U.S.N.M. 80919 was taken on Isle Vache by C. R. 

 Orcutt on June 5, 1929. A badly spoiled specimen, U.S.N.M. 

 84292, also from Isle Vache, was taken by L. H. Parish and 

 W. Perrygo in 1930. 



''Variation. — The specimens are uniformly melanistic, and the width 

 of the dorso-lateral light stripe is greatly reduced in all of them, so 

 that by this color character alone this subspecies may be told from 

 all the other related forms inhabiting Hispaniola and its neighboring 

 islets. The traces of a pair of narrow intermediate white lines are 

 almost lacking in two of the paratypes, and are less distinct in the 

 three others than in the type. In two of the paratypes the dorso- 

 lateral light stripe occurs only on the sixth scale row on the neck. 



"The ventrals vary between 148 and 153, the caudals between 

 115 and 131. A decided tendency towards having a single scale 

 in the second temporal series is noticeable, since two of the paratypes 

 resemble the type in having a single scale on one side of the head, one 

 paratype has a single scale on both sides of the head, while only two 

 specimens have the normal temporal count of 1 + 2 scales on both sides." 



Relationships. — The amount of melanism in L. p. rosamondae 

 from tie a Vache places it between L. p. lincolni, which has the light 

 stripes more undulating, and L. p. niger, in which the stripes are 

 almost entirely lacking. In position the stripes on the sixth, or sixth 

 and seventh, scale rows, correspond to L. p. tortuganus. In its low 

 scale-count, rosamondae seems to agree with some of the snakes 

 in the subspecies protenus having the lowest scale-counts. Its tend- 

 ency towards having a single scale in the second temporal series is a 

 character peculiar to this subspecies. It is on the whole an easily 

 recognizable form. 



