74 THE NAUTILUS. 
eyes in front of them and more separated. Mouth a vertical slit in 
a papillose disk. Swimming lobes arising at or behind the middle 
of the animal’s length, contiguous. Posterior subcircular area de- 
fined by a groove with smooth, raised anterior edge, and enclosing a 
cord. Mantle having a large shell-foramen and a long posterior 
siphonal fold. Genital orifice under the back part of the gill. 
Color (in aleohol) dark olive, or dull brown with more or less 
black maculation. In life it is said to be ‘a dark brown and the 
surface covered with warty papille.” 
Shell solid, with a brown cuticle. Apex with a roughened 
reflexed callus, continuing along the dorsal margins as a reflexed 
border over the cuticle. 
In external appearance, this species seems nearest to D. ecaudata 
and tongana, but the posterior area is defined by a far less conspic- 
uous frill, which does not extend to the edges of the dorsal slit. 
Dolabella guayaquilensis, a species known by the shell only, is stated 
to have the margins “scarcely reflected, callus small, narrow, not 
continued upon the margins,” while in the present species the mar- 
gins are bounded by unusually broad retlexed callous bands. Traces 
of sparsely scattered wart-like papillz are visible on some specimens, 
mainly posteriorly, but these are not very distinct in the alcoholic 
examples. Two of the original lot collected by Fisher are before 
me, the smaller one being drawn in my figure, and another specimen 
of a dark olive color collected by Dr. W. H. Jones on the “ West 
coast of Mexico,” has also been examined. 
DESCRIPTIONS OF NEW PISIDIA. 
BY DR. V. STERKI. 
In looking over more than 20,000 specimens of Pisidium, during 
the last twelve months, the writer came across numerous new forms, 
and many of them will prove to be new species. But, as some of those 
already published are not fixed beyond a doubt, owing to insufficient 
deseriptions and figures, and lack of reliable originals, and as new 
forms are constantly coming in, it will be advisable not to hurry 
with publications. Yet a few of these new species were seen from so 
many different places, and come to hand again and again that 
it is too unsatisfactory to return them without or only with MS. 
