tard 
THE NAUTILUS. 67 
The species has apparently heretofore been mistaken for O. rosa- 
lina, although the one is quite distinct from the other, especially so 
in general form, number of spiral whorls, and the non-appearance 
in QO. Blanesi of the rose colored base of the columella, which is sel- 
dom if ever absent in O. rosalina. 
A fine suite of these shells has been in my collection for several 
years, unnamed. Though convinced that they were an undescribed 
species they remained neglected until I recently found in the fine 
collection of Mr. Francisco E. Blanes, late of Cuba, a Jarge number 
of the same form mistakenly labelled O. rosalina Duclos. All, or 
nearly all of this entire lot had been collected by himself near Car- 
denas, Cuba. A brief explanation and comparison with genuine O. 
rosalina was sufficient to satisfy him of their distinct character, and 
the result is the new name, Olivella Blanesi. 
Specimens entirely white, secured at the same locality might well 
be termed var. alba. Some suspicion that these colorless shells 
might be identical with O. pura or O. bullula as figured by Reeve 
being felt, specimens were submitted by a friend to Mr. E. R. Sykes 
of London for comparison with Reeve’s types. To his kind assist- 
ance the following report is due: “I have compared your Olivella 
(with Mr. Smith’s ever ready helping hand). It does not seem to 
be either pura or bullula. Pura may not be the actual type, as it is 
recorded by Reeve as in ‘ Mus. Metcalfe.’ It is much more drawn out 
than your shell. The one specimen is in pretty good condition and 
seems never to have had much color marking, certainly not like 
yours. O. bullula here is snow white, but is thin and worn, so may 
have had some color. Itis slightly more elongate and does not show 
the sinus that your species has in the columella. Very probably 
yours is new.” 
A figure will be given later. 
AN INTERROGATION IN REGARD TO SEPTIFER BIFURCATUS RVE., 
AND MYTILUS BIFURCATUS CONR. 
BY MRS. M. BURTON WILLIAMSON. 
Shells that vary from the type sometimes raise a question in re- 
gard to the stability of their specific or generic values. Typical 
shells of Septifer bifurcatus Rve. and Mytilus bifurcatus Conr. are 
