, vel _Pentalepas_, 67.
_anseriferus_, 81.
_dentatus_, 73.
_dilatata_, 81.
_Donovani_, 92.
_fascicularis_, 92.
_Hillii_, 77.
_inversus_, 86.
_laevis_, 73, 77.
_radula_, 86.
_spirulae_, 86.
_spirulicola_, 92.
_sulcata_, 86.

_Pentalepas vitrea_, 92.

Poecilasma, Genus, 99.
aurantia, 105.
crassa, 107.
eburnea, 112.
fissa, 109.
Kaempferi, 102.

Pollicipes, 293.
cornucopia, 298.
elegans, 304.
mitella, 316.
_Mortoni_, 307.
_obliqua_, 264.
polymerus, 307.
_ruber_, 304.
_scalpellum_, 222.
sertus, 327.
_sinensis_, 375.
_Smythii_, 298.
spinosus, 324.
_tomentosus_, 274.
_villosus_, 274.

_Polylepas_, 215, 293.
_mitella_, 316.
_sinensis_, 375.
_vulgare_, 222.

Primordial valves, 22.

Prosoma, shape of, 39.

Proteolepas, 3, 26.

Pupa, locomotive or last larval state, in Cirripedes, 18.

_Ramphidiona_, 293.

Range, geographical, 65.

Rate of growth, 63.

Reinhardt on the burrowing of Lithotrya, 346.

Reproduction, organs of, in the Lepadidae, 55.

Rotifera, sexes of, 292.

Rules of nomenclature, 293.

Sack, description of, 31.
origin of, 15, 23.

Scalpellum, genus, 215.
_laevis_, 376.
_laeve_, 222.
_Sicilice_, 222.
ornatum, (female,) 244.
(male,) 248.
_papillosum_, 375.
Peronii, 264.
(male,) 270.
rostratum, 259.
(male,) 262.
rutilum, 253.
(male,) 258.
villosum, 274.
(male,) 278.
vulgare, 222.
larva of, 9.
(complemental male,) 231.
general summary on sexual relations, 281.

Schmidt, Dr., on chitine, 30.
on the muscles in young crustacea, 172.

_Senoclita_, 137.
_fasciata_, 146.

Sexes, discussion on, in Ibla and Scalpellum, 281.

Siebold, Dr. C. Von, 201.

_Smilium_, 215.
_Peronii_, 264.

Spermatozoa in Scalpellum vulgare, 236.

Sprengel, Ch. K., on compositous flowers, 203.

Steenstrup, Prof., on the homology of the peduncle, 26.
on the non-hermaphroditism of Cirripedes, 55.

Stomach of larva, 19.
general description of, 44.

Stroem on a seven-valved Lepas, 374.

Syngamus trachealis, 201.

Testes in the Lepadidae, 55.

_Tetralasmis_, 180.
_hirsutus_, 203.

_Thaliella_, 215.
_ornata_, 244.

Thompson, Mr. W., on Lepas anatifera, (v