26 SOLENODON PARADOXUS. 
a 
In the 6th vertebra this process is produced axially forming a broad ventro- 
lateral ridge extending posteriorly beyond the edge of the vertebra itself. This 
condition is found in Gymnura alba of which a skeleton was examined. In 
Erinaceus the posterior extent of this process is less. In the seventh cervical 
this large process is normally obsolescent, but in one example of Solenodon para- 
doxus examined, it is equally divided between the 6th and the 7th cervicals so 
that a vertebral canal is abnormally present on the left side of the 7th cervical, 
but not on the right side. 
The dorsal vertebrae in a general way resemble closely those of Gymnura. 
The spines of the three first dorsals increase successively in height, and measure 
from the anterior end of their proper bases, 11.5, 16, and 17 mm. respectively. 
These spines are high and somewhat circular in section, and expanded a trifle 
distally. In Gymnura the spine of the second dorsal is highest. The following 
spines from the fourth to the ninth decrease slightly in height, and become 
stouter and laterally compressed. All of the series are directed sharply back- 
ward. The spines of the tenth, eleventh, and twelfth vertebrae, however, are 
hardly tapered distally and curve distinctly forward at their tips. The thirteenth 
spine is nearly upright and the fourteenth is almost twice its length and points 
anteriorly. The two last dorsals have low spines whose tops are flat in profile 
and nearly as long as their centra. 
The twelfth dorsal vertebra begins to develop a descending lateral point at 
the posterior end, that becomes a distinct diapophysis at the 14th vertebra and in 
the vertebrae succeeding. Beginning with the first lumbar (Plate 7, figs. 13, 14) 
however, the diapophysis instead of being directed posteriorly, is curved anteri- 
orly from a base running the length of the vertebra on a level with the center 
of the spinal cord. 
The four sacral vertebrae are solidly fused throughout, much as in Gymnura, 
and the continuation of the diapophyses forms a flange or shelf along the sides of 
the centra. The dorsal profile is slightly emarginate between successive spines 
of the fused vertebrae. The sacrum, in dorsal view is narrower near the middle 
of its length than at either end. 
The caudal vertebrae (Plate 8, figs. 3, 4, 6) rapidly lose their dorsal spines, 
which are well developed in only the three first. The neural canal practically 
disappears with the ninth. The prezygapophyses of the fifth caudal are the 
last to form an articulation, for this and the succeeding vertebrae lack any 
trace of postzygapophyses. The prezygapophyses become successively reduced 
toward the tip of the tail, and become obsolete on the 16th or 17th vertebra. 
