156 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Material Examined. 
No. of 
M.C.Z. see Age Sex Locality Date Collector Remarks 
10918 1 adult male Watling’s Island 1909 W.W. Worthington Descrip. 
9272 1 adult male Watling’s Island 1903 J. H. Riley Para- 
type 
CYCLURA NUCHALIS, nov. sp. 
PlatesS; ands 2: 
Type, an adult, Acad. Nat. Sci. Phil. 11985, Fortune Island, Baha- 
mas. Collection of Arthur Erwin Brown. 
Since this species is in general similar to C. rileyi no detailed descrip- 
tion is necessary, the differences being expressed in the following 
diagnosis. 
Diagnosis:— Nasals broadly in contact with the rostral. Scales 
of the prefrontal and frontoparietal regions similar to those of C. 
riley; enlarged frontal scale proportionately larger, surrounding scales 
proportionally smaller than those of C. rileyi; supraorbital semicircles 
distinct posteriorly, formed of slightly tuberculate scales. Occipital 
scales more tuberculate than those of C. rileyi. Prefrontal scale 
more elongate than that of C. rileyi. Dorsal crest very different from 
that of any other Cyclura. This crest interrupted on the shoulders, 
widely interrupted on the rump; nuchal section formed of fourteen 
wide spines, the three central ones largest, about a centimeter high, 
the rest grading off in size toward the extremities; of these three 
central spines the most anterior one about half a centimeter wide at 
the base, in other words about twice as broad as any of the others; 
the crest running from shoulders to rump scarcely over a millimeter 
high, composed of sixty-two spines; caudal crest slightly higher than 
that of the back. Scales of the limiting row of each verticil only 
slightly larger than other scales of the verticil; about five scales in the 
bulge of each limiting row while C. rileyi averages four or less. The 
type of coloration similar to that of C. rileyi but the ground color 
brownish gray instead of blue-gray; general tonality of ite head gray- 
ish brown instead of straw color. 
Halhitat:— Fortune Island, just to the south of Lene Island, 
Bahamas. 
Material examined. 
The type only is known. 
