342 _ PROCEEDINGS OF THE ACADEMY OF [May, 
Length 12.6, diam. 4 mm.; whorls 133 
ec 12:5, ag 4 a3 ce 123 
gp Shire! hs ere . ‘* 12; an axial lamella. 
These shells connect H. crossei and H. bilamellata. Specimens 
of intermediate size agree exactly with one of the type lot of mearnsi, 
kindly lent from the National Museum. The smallest shells are 
indistinguishable from crossei, while the largest could not be separated 
from small bilamellata. Yet the colony as a whole has a certain 
individuality by its intermediate size, and as the form has been named, 
we let it stand as a convenient place for crossei-bilamellata inter- 
grades. It is attached to H. bilamellata rather than to H. crossei, 
because the prevalent form, in the small lot opened, is bilamellate. 
All of the shells were collected in one spot where the writer sat 
resting. A large quantity could have been gathered had time and 
strength permitted. A few specimens are quite finely striate, 
while others are rather coarsely ribbed, like the type of mearnsi; 
still others being intermediate in sculpture. The sculpture in 
some shells becomes very much weaker on the penultimate and 
next earlier whorls. 
H. mearnsi served as monotype of the subgenus Haplostemma 
Dall, characterized by the possession of an axial lamella only. Bartsch, 
opening another specimen, found a basal lamella also, and concluded 
that that lamella had been broken away in opening the original 
specimen. Since some fully adult examples are known to have an 
axial lamella only, it is likely that Dall’s original diagnosis was 
correct for the specimen he opened, while Bartsch was also right 
as to the shell he examined and which we have seen. 
Holospira crossei Dall. Plate VII, figs. 7 to 7c. 
Holospira crosset Dall, Proc. U. S. Nat. Mus., XVIII, 1895, p. 3; XIX, 
1897, p. 348, Pl.31, fig. 2. Pilsbry, Man. of Conch., XV, p. 92, Pl. 28, 
fig. 75; Moll. S. W. States, ii, Proc. A. N. S. Phila., 1905, p. 217, Pl. 26, 
fig..8. Bartsch, Proc. U.S. Nat. Mus., XX XI, 1906, p. 137. 
All of the above references were based upon the original lot, of 
which there are 11 perfect specimens in Coll. U.S. Nat. Mus. and 2 
in Coll. A.N.S.P. One of these two has a very weak, hardly notice- 
able fold on the axis, the other has a very strong but short fold 
there. 
The writer collected H. crossei at the type locality, the summit 
of Hacheta Grande. The exact spot, Station 11, is just off the 
western edge of the small level tract at the summit, which is marked 
by a small stone monument. Being much higher, this station is 
less dry than Station 5, where the large H. bilamellata abounds, and 
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