298 
propose to name it sectio Rostrato-verruca, owing to its prominent 
rostrum. Indeed, this character seems to be more important, and 
lends the species a more aberrant feature than any other of the 
characters used by Pilsbry as means of distinction between his 
sections of the genus Verruca. 
Family Chtamalidae. 
Genus Catophragmus Sowerby. 
Catophragmus Pilsbryi n. sp. 
Taboga, Panama, on Coastal rocks in the tidal zone. 12/XII 15. Several 
specimens. 
a 
Fig. 45. Catophragmus Pilsbryi from Taboga, Panama, a type specimen in natural 
size, b carina of another specimen, outside, c the same, inside, 
d the same, top view. [b —d X 2]. 
The eight principal plates of the wall indistinct; supplementary 
compartments very numerous, irregular, imbricating over the sut¬ 
ures. The chitinal layer not reaching the basal edge of the com¬ 
partments; all plates of the wall with several longitudinal ridges, 
with crenulated margins; summits corroded. Caudal appendages 
present, almost as long as the protopodite of cirrus VI, with 6 
segments. Basis unknown. (Subgenus Catophragmus Pilsbry). 
The shell is broad and low (Fig. 45). The inner whorl of plates 
is little distinet, generally even less distinetly pronounced than in 
the specimen figured; especially the rostral latera may be difficult 
to trace in many cases. Although the outer compartments gener¬ 
ally decrease in size towards the periphery of the wall, this is not 
without exceptions, and the animal thus often attains a rather ir¬ 
regular aspect. From below the appearance is more regular,'although 
