1891.] On the Genus Chlamydophorus. 543 
shield the specimen should be before one. Without this aid, 
and even with the assistance of drawings, the admirable descrip- 
tion of Professor Hyrtl can with difficulty be comprehended. 
But I have no better resource than to translate his words: 
“Three longitudinal crests spring up from the dorsum of the 
sacrum, of which the middle one absorbs, as it were, the two lat- 
eral, at a point just behind the ischiatic foramen ; thus only one 
remains. This, in the shape of a long, perpendicular, thin, pellu- 
cid plate, perforated in many places, is produced throughout the 
entire length of the sacrum, and posteriorly is lost in the sphee- 
roma. The middle crest at the spot where the meeting of the 
lateral ones produces a bony mass is transformed into a*bony 
transverse plate, which is connected on either margin with a long 
and unusual process of the ischium, which I call the ascending. 
rim 
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Fic: 2.—Chlamydophorus truncatus Harl. ; two-thirds natural size; skeleton. 
From the dorsal face of the transverse lamina two round, bony 
columns rise and become supports to the sphceroma. Thus this 
wonderful sphceroma is tonnected to the pelvis by five fulcra. 
The two first and principal ones arise from the ischia, the two 
middle are the two columns erected on the transverse lamina of 
the sacral crest, and the highest is the termination of the median 
crest.” 
Since the strongest fulcra of the shield are found in the place 
Where in other Dasypodidæ the tubeta ischii reside, it would 
seem evident that this unusual structure springs from the conflu- 
ence of the tuberosites. Its shape is that of a semi-circular disc, 
with its convex margin upwards, which is thicker than the lower 
Am. Nat.—June.—3, 
