I : 
GENERAL CLASSIFICATION. Moll^ 19 
dudes the Chitonidm with Chcetoderma (Lov4n) and Neomenia 
(Tullberg),*^ but as a distinct “class.” 
Molluska {sic)i Phylum 1. Acephala (Cuv.) = Lamellihranchia 
(Blainv.). 
Phylum 2. Solenoconchas (Lacaze-Duthiers). 
Phylum 3. Arthrocochlides (new), corresponding partly to the 
Prosohranchia (M.-Ed.). Cerebral, pedal, commissural, and vis- 
ceral ganglions are present, and their commissures form an anterior 
and a posterior ring round the pharynx ; the arteria pedalis never 
lying between both rings. 
First “class.’' Ciiiastoneura (new).j A supra-intestinal ganglion 
depending from the dextral commissural ganglion, but situ- 
ated on the left side, and giving nerves to the left half of 
the body ; a sub-intestinal ganglion depending from the left 
commissural ganglion, situated on the right side, and giving 
nerves to the right side of the body. 
Ord. 1. Zeugorranciiia : Fissurellidee, Haliotides, and Pleuroto- 
maridoe. 
Ord. 2. Anisobranchia. 
Suborder 1. Patelloidea (Docoglossa, Troschel). 
Suborder 2. Rhipidoglossa (Troschel, part) : Trochidaa. 
Suborder 3. Tcenioglossa (Troschel, part) : Littorinidse, Cyclo- 
stomidse, Melaniidae, Turritellidae, &c. 
Second “class.” Orthoneura (new). The visceral nervous system • 
forms a simple noose round the intestine, the nerves remain- 
ing limited to the side of the body in which they have their 
origin. 
Ord. 1. Rostrifera (Gray, part). 
Suborder 1. Rhipidoglossa (Troschel, part) : Neritacea, Helici- 
nacea, and Proserpinacea. 
Suborder 2. Ptenoglossa (Troschel) ; Janthinidae, Solariidae, 
and Scalariidae. 
Suborder 3. (Troschel, part) : Ampullariidoa, Val- 
vatidae, Capuloidea, Sigaretina, Cypraeidae, Cerithiacea, 
Alata. 
Ord. 2. Proboscidifera (Gray), with three suborders Taenio- 
glossa (Troschel, part), Toxoglossa, and Rhachiglossa . 
(Troschel). 
Ord. 3. Heteropoda (Lam.) 
Phylum 4. Platycochlides (new). Central part of the nervous 
system consisting either of a simple mass, or of cerebral, pedal, and 
visceral ganglions ; arteria pedalis situated between the visceral 
and pedal ganglions, if the former is separated from the cerebral 
ganglion. Sexes mostly united. 
First “ class.” Ichnopoda (new). 
Ord. 1. Protocochlides (new). Only a dorsal ganglion. No 
radula ; Rhodopidae, Tethydae, Melibidae. 
* For Neomenia , see Zool. Eec. xii. p. 544 { Vermes ). — Rec. 
