REPORT ON THE PTEROPODA. 
73 
An attentive examination of this superfluity of titles shows that there are amongst 
them only eight genuine species, all obtained on the Challenger Expedition. 
All the other titles are synonyms of these eight species. It is necessary, however, 
to distinguish : — 
1. Thirteen titles referring to the young stages of several of these eight forms : — 
Hyalsea complanata, Gegenbaur, 
Hyalsea depressa, d’Orbigny, . 
Hyalsea laevigata, d’Orbigny, 
Hyalsea rotunda ta, Boas, 
Hyalsea rugosa, d’Orbigny, 
Hyalsea truncata, Lesueur, 
Cleodora compressa, Souleyet, . 
Cleodora curvata, Souleyet, 
Cleodora pygmsea , Boas, 
Cleodora trijilis, Troschel, 
Pleuropus hargeri, Yerrill, 
Pleuropus longiJUis, Troschel, . 
Pleuropus pellucidus, Eschscholtz, 
2. Four titles which may be applied to 
Hyalsea affinis, d’Orbigny, 
Hyalsea costata, Pfeffer, 
Hyalsea labiata, d’Orbigny, 
Hyalsea truncata, Krauss, 
= Cavolinia tridentata, Forskal. 
= Cavolinia injlexa, Lesueur. 
= Cavolinia longirostris, Lesueur. 
= Cavolinia globidosa, Rang. 
= Cavolinia gibbosa, Rang. 
= Cavolinia sp. 
= Cavolinia trispinosa, Lesueur. 
= t Cavolinia uncinata, Rang. 
= Cavolinia quadridentata , Lesueur. 
= Cavolinia sp. 
= Cavolinia gibbosa, Rang. 
= Cavolinia tridentata, ForskSl. 
= Cavolinia injlexa, Lesueur. 
>cal varieties of some species : — 
= var. of Cavolinia tridentata. 
= var. of Cavolinia quadridentata. 
= var. of Cavolinia injlexa. 
= var. of Cavolinia tridentata. 
3. All the other titles are absolutely synonymous 
species : — 
Hyalsea angulata, Souleyet, 
Hyalsea australis, Peron, 
Hyalsea chemnitziana,!* eron and Lesueur, 
Hyalsea cornea, Lamarck, 
Hyalsea cumingii, Sowerby, 
Hyalsea cuspidata, Delle Chiaje, 
Hyalsea depressa , Bivona, 
Hyalsea ecaudata, Lesueur, 
Hyalsea elongata, Lesueur, 
Hyalsea femorata, Gould, 
Hyalsea jissirostris, Benson, 
(ZOOL. CHALL. EXF. PART LXV. 1887 .) 
with those of the eight genuine 
= Cavolinia longirostris. 
> 
• = Cavolinia tridentata. 
| = Cavolinia trispinosa. 
= Cavolinia longirostris. 
= Cavolinia injlexa. 
j = Cavolinia longirostris. 
Ttt 10 
