Con foil ii(Ji 11(1 iif}\iisNii 1 n I'lftiitii . — Iltiii'f. 175 
turn, Sa}'. ' * Tuomey and Holmes" use of this designation fifteen 
years later in their Pliocene Fossils of South Carolina seems 
correct insomuch as both the description and the figure they give 
indicate a species identical with Says X. tridttntd.l 
In his catalogue of the Miocene Shells of the Atlantic Slope, 
Conrad questions the identity' of the Miocene •'•Tritia (^Xnnsa) 
fn'vitfnfa' with the specimens referred to by Say. Tuome}' and 
Holmes. || 
The following reference occurs in Meeks Checklist ot Miocene 
Invertebrates, published in 1864:*! 
•'683. Tritia t ric ittnta {iiay'^) i^onnid. Md. ; Va. ; S. Car. The 
Maryland and South Carolina forms are here confused and con- 
sidered identical. The specimens in the collection of the U. 
S. National Museum, from St. Mark's river bear the name ■■Tritin 
trivittatum. Say"' in Meeks hand-writing; the identification is 
moreover initialed l)y Heilprin. 
In 1867, Conrad described a new species under the name ot 
Ptycliosalpinx {Tritin ro) peraJta.^* Although no locality is given 
for this species, the description, the figure, and the facts that it 
is a Miocene form and is, according to Conrad, the equivalent of 
Tritin trivittata Conrad (not Say) leave little room for doubting 
that the species here described is that occurring so abundantly in 
the vicinit}' of St. Marys river. Maryland. 
Heilprin has overlooked this name altogether in his Tertiary 
Geolog}- of the United States, published in 1884. and continues 
to refer this Miocene form to Xnssn tricittatn Say. ti He uses the 
same designation in his list of .Miocene species of Xew Jersey, 
j)ublished in the Proceedings of the Philadel})hia .Vcadomy of 
Natural Sciences, 1887. t but whether in this case rtijclmsnlitiii.r 
(Tritiaru) prrafta (more \noperly Xaxga peralta) or Xassa tririt- 
ttttoitlf'-s Whitf'd (MS.) is referred to, one cannot decide without 
seeing the specimens themselves. 
Professor Clark of Johns Hopkins T'niversity has also over- 
looked Conrad's X. pcraltd. for, in 1888.t and again in 1S!»1 he 
refers this form to Xnssn tricittdta of Say. 'i 
The foregoing facts maj' be thus summarized: — 
*2d Bull. Proc. Nat. Inst., 1842. p. 186. Proc. Phila.Ac. Nat. Sci. 1862, p. 562. 
^Op. rit. P. 185, pi. 28, titr. 4. t+Op. cit pp. o8 & 61. 
• Smithsn. Mi-rl. Coll. No. 18:5. p. 20. 1!», tig. o. 
**Amer. .lour. Conch., iii, p 264, pl.tOp. cit. pp. 398, 401. 
JJ. H. Univ. cir. vii. p. 66. Jjlbifl.. x. p. 107. 
