MONOGRAPH OF THE GENES STIiOPHIA. 161 
strongly marked species, but it occurs in the fields on the south side 
of the Creek where it completely intergrades, through a small 
percentage of specimens with typical S. glans ; hence I have been 
forced to consider it a sub-species. 
The Gray Acorn Strophia may be known at once by the thick, 
grooved margin, and peculiar uniform gray color which I have not 
seen in any other form of Strophia. 
HABITS AND DISTRIBUTION. 
The first specimen of the Gray Acorn Strophia that I ever saw 
were brought to me by some Creole boys, but I soon discovered the 
typical locality, which were some fields north of the creek, about a 
mile from the settlement, and by the side of the road which leads 
northward to Calabash Bay. Here they were not common and were 
clinging to the bushes along the margin of the cultivated fields. 
South of the creek the few that I found were also clinging to bushes 
either in the fields or along the borders, but here they were even more 
rare than in the type locality. These specimens on the south side were 
undoubtedly transplanted from the north side through the agency of 
the inhabitants, who pass from one set of fields to the other, carrying 
with them the plants of the casava on which the Strophias frequently 
occur. 
47 STROPHIA REGULA Novo. 
Regular Strophia, 
Fig. 52, A, side, B, front view of type. 
DESCRIPTION. 
Sp. Cli. Size, large. Shell, not very thick. Striations present. 
Whirls, twelve. Examined fifty specimens. 
Form of shell a pointed cylinder, with the first, second and third 
whirls about equal in diameter, the fourth is but a little smaller, then 
the shell slopes to an acute point, forming an angle of sixty-two 
degrees. The first whirl is comparatively short, being only as long 
(measured in front) as the next four whirls below it, all together. The 
second whirl is shorter than the third and fourth, together, then each 
successive whirl is shorter than the next two below it. The striations 
are numerous, tw r enty-nine to the first whirl, they are narrow', about as 
wide as the interspaces between them, are rather angular, but are 
