MONOGRAPH OP THE GENUS STROPHIA. 
9 
The color of the shell of S. eurystoma is yellowish white, externally, 
with the apex flesh color. Internally, pale brownish or flesh, fading into 
yellowish 'white on the teeth and margin. It is worthy of note that 
shells of the typical form, show stainings ofared ochraceous earth, while 
those which I have mentioned as form No. 1, are either stained with a 
brown earth or are without staining, hence it is reasonable to suppose 
the forms do not occur together. Should this prove true, form Ho. 1 
must take subspecific rank, in which case it may be called Stropbia 
eurystoma ignota. 
SUBGENUS 7. TRX DEN TI STROPHIA. 
Lower tooth central, elongated, being at least three times 
AS LONG AS HIGH. BEHIND THIS ARE TWO OTHER TEETH WHICH EXTEND 
BACK INTO THE SHELL, BUT NO FURTHER THAN ONE-HALE THE LENGTH OF 
the first whirl. Type, Strophia striatella Ferussac, Habitat, Cuba. 
This singular system of teeth recalls the channeled tooth of Dia- 
cerion, but differs in not extending as far back 
into the shell, and in having three distinct 
teeth, the outer of which is shorter than the in- 
ner, and often not being longer than the middle 
or front tooth. See Fig. 1, A, where I have 
given a cut of the teeth of Tridentistrophia 
( S. striatella ) and compare with ib b, where I 
have given a figure of the channeled tooth of 
Diacerion. Other characters of Tridentistrophia 
are, striations numerous ( SO or 40 to the first whirl) ; margin, thick 
and rounded never beveled ; shell, less than three times its width in 
length ; whirls, short, but the upper is as wide as at least all of the next 
six following. 
60 STROPHIA STRIATELLA Ferussac. 
Striped Strophia. 
Plate II, fig. 5, front, fig. 6, side view of type. 
Pupa striatella Ferussac, Hist. Nat. des Moll. Page 206, plate 159, 
fig. 11 and 13 ; 1820-1851. 
DESCRIPTION. 
Sp. Ch. Size small ; shell quite thick. Whirls 6. Examined 25 
specimens. 
A, tooth of a Tridenti- 
strophia. b, tooth of 
Diacerion, both enlarged. 
