290 0. C, Marsh—Dermal Scutes of Mosasauroid Reptiles, 
Off South-end, near New Haven, 1-4 fathoms, common, 
—A. V.; Vineyard Soe, cpa ‘and Great Bog Harbor, 
N. Tiel. K. V., and 8. L Sm 
Errata.—p. 210, for saat cerinum, read Mangelia cerina. 
EXPLANATION OF PLATES. 
PuLaTE VI. 
Figure 1. ag aides enlarged 5 oo ; 1 a, the same, natural size (from 
nney’s Gould, by E. 8. Mor 
2. Angulus mode us V., enlarged 5 ai ameters ; 2a, the same, natural size. 
ete oe hari v. enlarged 16 diameters ; 3a, another specimen, 
= eae ser num = hae ature, enlarged 24 diameters 
“7, Styliola vitrea V., enlarged 3 di diameter 
oO 
=] 
— 
= 
“8 
a 
3 
5 - =") 
Se 
Le eee ee 
LEN ee ee 
Figure 1. Periploma Eevyrcoes, left side, exterior view (from Binney’s Gould, by E. 
8. Morse); La, the same, view of the interior of a young specimen, with 
the ossicle in place, enlarged 3 diameters; 10, ossicle of the same, 
enlarged 30 diameters. 
ie ‘ todon V., enlarged 3 diamet 
“8. Modiola hamatus tee: rom New Have n, enlarged nearly 2 diameters. 
“ 4. Turtonia nitida V., view of the saterlot, aulerg bl 40 diameters ; 44, the 
same, hat view, natural size and enlarged, (from Binney’s Gould, by 
E. 8. Mors 
“* 5. Elysiella ati V., dorsal view, sinter nearly 83 diameters; 5a, the 
same, ventra fe teers e0 nlarged 
Puate VIII. a 
Figure 1. potty orepe papyracea, papas resting in right valve wie Be of the man- 
e Femoved fom ¢ the upper side; a, retracted a ‘nal tube; , branchial 
3 m,m, anterior and posterior addu ett muscles ; 4, intes- 
snes ee o pal i of left side; 7, retracted foot; 0, openi 
tle for protrusion 0 of foot 
He 12. Mol iD rebar more than natural s : a 4 
—- Bugyra po tad +. enlarged about 2 ne “with the adhering m ; 
partly removed. e 
“ 4. Molgula papillosa V., from off Martha’s Vineyard, enlarged 2 diamete 18 
with t hering sand mostly af 
“ 5, Molgula arenata Stimp., natural size, and with its coating of sand. 
eC. Me ueta Stimp., natural size, with its coat of fine sa 
t 
“7. Cynthia partita Stimp., erect variety, showing the outline and the go 
ter of the apertures; but the surface of the body appears smoot other 
is natura 
one, Ascidiopsis com ee mata V., small portion of the gill, much enlarged. 
’ a V., from Murray Bay, enlarged 3 diameters. with 
uae Aleyoion ramosum V.,a young specimen enlarged 2 diameters, 
of the zooids expanded. 
Art. XXXIX. a of the Dermal — = Mosasauroid 
Reptiles ; by Professor O. C. Mar 
THE great abundance of Pythonomorpha in the Crete 
deposits of this country is rapidly affording material hess t 
understanding of the structure of these peculiar reptiles, abou 
which, _ recently, so little has been known. The arent 
tions of the Yale Coliege party in Western Kansas, 1 L he 
first proved the existence of posterior limbs, in three of * 
